Amazon Selling Partner

### App
Amazon Selling Partner

### Summary:
Authenticated SP-API actions fail when called through Perplexity

### Details:
I am using the Pipedream Amazon Selling Partner integration through a Perplexity connector.

The connector is shown as CONNECTED. The marketplace option action successfully returns Amazon.com with Marketplace ID ATVPDKIKX0DER, but authenticated SP-API actions fail with this error:

Session is not authenticated for the connector service.

Test operation:
- Action: Check FBA Inventory Levels / getInventorySummaries
- Marketplace ID: ATVPDKIKX0DER
- Seller SKU: [REDACTED SELLER SKU]
- details: true

Steps already completed:
1. Signed in to Pipedream.
2. Connected the Amazon Selling Partner account.
3. Approved the requested permissions in Amazon Seller Central.
4. Confirmed the connected account in Pipedream.
5. Removed and recreated the connector in Perplexity.
6. Retried the request, but the same error persists.

Please check:
1. Whether the Amazon connected account and OAuth refresh token were stored successfully.
2. Whether the account is attached to the Pipedream Connect/MCP session used by Perplexity.
3. Whether this is a session-binding issue between Pipedream and Perplexity.
4. Whether a paid Pipedream plan or a specific project/environment is required.

This request is for Amazon.com US only. No CA, MX, or other marketplaces are being used.

### Screenshots:
No screenshots included

No source files, tests, or entry points are identified in the report. Start by reproducing the getInventorySummaries request through the Perplexity connector with the Amazon.com marketplace, then investigate account, refresh-token, and MCP session association. Done means determining the session-binding cause and documenting or implementing a verified resolution.

Written by the indexing model from the issue text.