[Bug] [TC-CNET-4.12] Test consistently failing at Connecting the 2nd thread network(Step 7) with timeout error in TH GUI

Describe the bug

The test case TC-CNET-4.12 is consistently failing at Step 7 during execution in TH GUI. TH sends ConnectNetwork command to the DUT with NetworkID field set to PIXIT.CNET.THREAD_2ND_OPERATIONALDATASET and Breadcrumb field set to 2. But the device didn't connect to the 2nd Thread network. The failure occurs due to a timeout issue, even after multiple reruns under stable network conditions.

Issue Details:

[MatterTest] 10-16 06:35:30.290 ERROR Exception occurred in test_TC_CNET_4_12.
Traceback (most recent call last):
File "/usr/local/lib/python3.12/dist-packages/mobly/base_test.py", line 801, in exec_one_test
test_method()
File "/usr/local/lib/python3.12/dist-packages/matter/testing/decorators.py", line 369, in per_endpoint_runner
test_instance.event_loop.run_until_complete(asyncio.wait_for(
File "/usr/lib/python3.12/asyncio/base_events.py", line 687, in run_until_complete
return future.result()
^^^^^^^^^^^^^^^
File "/usr/lib/python3.12/asyncio/tasks.py", line 520, in wait_for
return await fut
^^^^^^^^^
File "/root/python_testing/scripts/sdk/TC_CNET_4_12.py", line 365, in test_TC_CNET_4_12
resp = await self.send_single_cmd(
^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/dist-packages/matter/testing/matter_testing.py", line 1054, in send_single_cmd
result = await dev_ctrl.SendCommand(nodeid=node_id, endpoint=endpoint, payload=cmd, timedRequestTimeoutMs=timedRequestTimeoutMs,
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/usr/local/lib/python3.12/dist-packages/matter/ChipDeviceCtrl.py", line 1643, in SendCommand
return await future
^^^^^^^^^^^^
matter.exceptions.ChipStackError: src/app/CommandSender.cpp:354: CHIP Error 0x00000032: Timeout
[MatterTest] 10-16 06:35:30.310 ERROR

---

• Test test_TC_CNET_4_12 failed for the following reason:
• src/app/CommandSender.cpp:354: CHIP Error 0x00000032: Timeout
• File "/usr/local/lib/python3.12/dist-packages/matter/ChipDeviceCtrl.py", line 1643, in SendCommand
• matter.exceptions.ChipStackError: src/app/CommandSender.cpp:354: CHIP Error 0x00000032: Timeout
• Test step:

• 7: TH sends ConnectNetwork command to the DUT with NetworkID field set to PIXIT.CNET.THREAD_2ND_OPERATIONALDATASET and Breadcrumb field set to 2	Expected outcome: Wait for device to connect to the Thread network. A wait time of `connect_max_time_seconds + fudge_factor_seconds` is applied to allow Thread network connection and SRP record propagation
  

• Endpoint: 0

Steps to reproduce the behavior

1. Open the TH GUI.
2. Upload the relevant PICS file for Network commissioning cluster.
3. Update the UI configuration as mentioned below:
   "endpoint": "<device_endpoint>",
   "string-arg": "PIXIT.CNET.THREAD_2ND_OPERATIONALDATASET:<thread-data-set_2>"
4. Ensure the TC-CNET-4.12 test case is selected.
5. Make sure the DUT is advertising. (QA has used nRF52840-DK board as DUT)
6. Click the Start button on Test-Harness user interface.

Expected behavior

The test case should be run completely and PASS without any issues.

Log files

TH GUI Controller log for reference:
Test Run1: TC-CNET-4_12_2025_10_15_16_09_29.log
Test Run2: TC-CNET-4_12_2025_10_16_06_33_07.log
Test Run3: TC-CNET-4_12_2025_10_16_12_07_54.log

DUT log for reference:
Test Run1: TC-CNET-4_12-TH-Failure-DUT_log.txt
Test Run2: TC-CNET-4_12-THGUI-Failure-DUT_log.txt
Test Run3: TC-CNET-4_12-THGUI-Failure-DUT_log2.txt

PICS file

Network Commissioning Cluster Test Plan(Thread).xml

Screenshots

Environment

TH Version: v2.14-beta3+fall2025
Sha: 24f227f

Start with scripts/sdk/TC_CNET_4_12.py around line 365 and inspect the provided TH GUI and DUT logs for the Step 7 timeout in SendCommand. Reproduce with the documented TH GUI configuration and nRF52840-DK setup, then verify that TC-CNET-4.12 completes and passes without the connection timeout.