Trying to use a Zoho Billing connector with the but sync is failing

### Connector Name

zoho billing

### Connector Version

0.0.44

### What step the error happened?

During the sync

### Relevant information

Tried many times to sync the data but everytime it gives the same error.

### Relevant log output

```shell
Sync failed

0 bytes
|
no records loaded
|
3m 17s
Failure in source: Checking source connection failed - please review this connection's configuration to prevent future syncs from failing

Feb 19, 2026, 2:57 PM

Sync started

Congnitics manually started a sync
Feb 19, 2026, 2:54 PM

Connection settings changed

Congnitics added a stream prefix: "zoho_billing_" and 2 other changes.
View details

Feb 19, 2026, 2:49 PM

Feb 19
Logs: acme_inc_zoho_billing

Attempt 2 of 2
Feb 19, 2026, 2:57 PM
|
0 bytes
|
no records extracted
|
no records loaded
|
Job id: 71384496
|
20s

Failure in source: Checking source connection failed - please review this connection's configuration to prevent future syncs from failing
Search logs

Log sources

4

Log levels

5
2026-02-19 14:57:54 source ERROR Encountered an error while checking availability of stream Products. Error: 400 Client Error: for url: https://accounts.zoho.com/oauth/v2/tokenError traceback:
Traceback (most recent call last):
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/checks/check_stream.py", line 113, in _check_stream_availability
stream_is_available, reason = evaluate_availability(stream, logger)
~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/checks/check_stream.py", line 26, in evaluate_availability
availability = stream.check_availability()
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/concurrent/default_stream.py", line 117, in check_availability
next(iter(partition.read()))
~~~~^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/stream_slicers/declarative_partition_generator.py", line 91, in read
for stream_data in self._retriever.read_records(
~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
self._schema_loader.get_json_schema(), self._stream_slice
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
):
^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/retrievers/simple_retriever.py", line 460, in read_records
yield from self._read_pages(record_generator, _slice)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/retrievers/simple_retriever.py", line 398, in _read_pages
response = self._fetch_next_page(stream_slice, next_page_token)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/retrievers/simple_retriever.py", line 315, in _fetch_next_page
return self.requester.send_request(
~~~~~~~~~~~~~~~~~~~~~~~~~~~^
path=self._paginator_path(
^^^^^^^^^^^^^^^^^^^^^^^^^^
...<22 lines>...
log_formatter=self.log_formatter,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
)
^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/requesters/http_requester.py", line 467, in send_request
headers=self._request_headers(
~~~~~~~~~~~~~~~~~~~~~^
stream_state, stream_slice, next_page_token, request_headers
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
),
^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/requesters/http_requester.py", line 315, in _request_headers
headers = self._get_request_options(
stream_state,
...<4 lines>...
extra_headers,
)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/requesters/http_requester.py", line 298, in _get_request_options
auth_options_method(),
~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 93, in get_auth_header
token = self.access_token if self._is_access_token_flow else self.get_access_token()
~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 109, in get_access_token
self.refresh_and_set_access_token()
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 120, in refresh_and_set_access_token
token, expires_in = self.refresh_access_token()
~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 182, in refresh_access_token
response_json = self._make_handled_request()
File "/usr/local/lib/python3.13/site-packages/backoff/_sync.py", line 105, in retry
ret = target(*args, **kwargs)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 267, in _make_handled_request
response.raise_for_status()
~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/requests/models.py", line 1026, in raise_for_status
raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 400 Client Error: for url: https://accounts.zoho.com/oauth/v2/token
Traceback (most recent call last):
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/checks/check_stream.py", line 113, in _check_stream_availability
stream_is_available, reason = evaluate_availability(stream, logger)
~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/checks/check_stream.py", line 26, in evaluate_availability
availability = stream.check_availability()
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/concurrent/default_stream.py", line 117, in check_availability
next(iter(partition.read()))
~~~~^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/stream_slicers/declarative_partition_generator.py", line 91, in read
for stream_data in self._retriever.read_records(
~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
self._schema_loader.get_json_schema(), self._stream_slice
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
):
^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/retrievers/simple_retriever.py", line 460, in read_records
yield from self._read_pages(record_generator, _slice)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/retrievers/simple_retriever.py", line 398, in _read_pages
response = self._fetch_next_page(stream_slice, next_page_token)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/retrievers/simple_retriever.py", line 315, in _fetch_next_page
return self.requester.send_request(
~~~~~~~~~~~~~~~~~~~~~~~~~~~^
path=self._paginator_path(
^^^^^^^^^^^^^^^^^^^^^^^^^^
...<22 lines>...
log_formatter=self.log_formatter,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
)
^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/requesters/http_requester.py", line 467, in send_request
headers=self._request_headers(
~~~~~~~~~~~~~~~~~~~~~^
stream_state, stream_slice, next_page_token, request_headers
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
),
^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/requesters/http_requester.py", line 315, in _request_headers
headers = self._get_request_options(
stream_state,
...<4 lines>...
extra_headers,
)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/declarative/requesters/http_requester.py", line 298, in _get_request_options
auth_options_method(),
~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 93, in get_auth_header
token = self.access_token if self._is_access_token_flow else self.get_access_token()
~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 109, in get_access_token
self.refresh_and_set_access_token()
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 120, in refresh_and_set_access_token
token, expires_in = self.refresh_access_token()
~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 182, in refresh_access_token
response_json = self._make_handled_request()
File "/usr/local/lib/python3.13/site-packages/backoff/_sync.py", line 105, in retry
ret = target(*args, **kwargs)
File "/usr/local/lib/python3.13/site-packages/airbyte_cdk/sources/streams/http/requests_native_auth/abstract_oauth.py", line 267, in _make_handled_request
response.raise_for_status()
~~~~~~~~~~~~~~~~~~~~~~~~~^^
File "/usr/local/lib/python3.13/site-packages/requests/models.py", line 1026, in raise_for_status
raise HTTPError(http_error_msg, response=self)
requests.exceptions.HTTPError: 400 Client Error: for url: https://accounts.zoho.com/oauth/v2/token
2026-02-19 14:57:54 source ERROR Check failed
2026-02-19 14:57:54 platform INFO Checking for optional control message...
2026-02-19 14:57:54 platform INFO Writing output of 09c98db2-9ccc-4a5c-bf06-1ca31f626c1c_71384496_1_check to the doc store
2026-02-19 14:57:55 platform INFO Marking workload 09c98db2-9ccc-4a5c-bf06-1ca31f626c1c_71384496_1_check as successful
2026-02-19 14:57:55 platform INFO Deliberately exiting process with code 0.
2026-02-19 14:57:55 platform INFO
2026-02-19 14:57:55 platform INFO ----- END CHECK -----
2026-02-19 14:57:55 platform INFO
2026-02-19 14:57:56 platform INFO Retry State: RetryManager(completeFailureBackoffPolicy=BackoffPolicy(minInterval=PT10S, maxInterval=PT30M, base=3), partialFailureBackoffPolicy=null, successiveCompleteFailureLimit=5, successivePartialFailureLimit=1000, totalCompleteFailureLimit=5, totalPartialFailureLimit=20, successiveCompleteFailures=2, successivePartialFailures=0, totalCompleteFailures=2, totalPartialFailures=0)
Backoff before next attempt: 30 seconds
2026-02-19 14:57:56 platform ERROR Failing job: 71384496, reason: 'Encountered an error while checking availability of stream Products. Error: 400 Client Error: for url: https://accounts.zoho.com/oauth/v2/token'
```

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