Valid Facebook Graph Access Token fails with a 400 Bad Request error

Questions
1

Hello n8n Support Team,

I am unable to save or use my Facebook Graph API credentials on my n8n Cloud instance. Every attempt fails with a 400 Bad Request error.

The specific error from Facebook is OAuthException, code 2500, with the message: "An active access token must be used to query information about the current user."

  1. The Access Token is Valid: I have repeatedly verified the token using the official Meta for Developers Access Token Debugger. It shows the token is valid, active, long-lived (expires in 2025), and has all the required scopes, including instagram_business_content_publish.

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  2. Ruled out User Error: meticulously checked for copy-paste errors, hidden whitespace, and browser cache/extension issues.

  3. Direct API Tests Failed: Bypassed the credential manager and used an HTTP Request node to make direct API calls. Both a GET request to /me and /me/accounts failed with the exact same OAuthException 2500 error.

Conclusion: The evidence strongly suggests that Facebook’s API is rejecting my valid token because the requests are originating from my n8n Cloud instance’s IP address. The token works perfectly in the debugger (from my IP) but fails from n8n’s server IP.

Could you please investigate if there are any known issues with your server IPs and the Facebook/Instagram Graph API?

Thank you for your help.

2

Welcome to the community @Supatoiki

The way to bypass this IP restriction is to not let n8n Cloud make the API call itself. Instead, you will configure n8n to tell Facebook to send data to a public, custom URL that you own. This makes the request originate from your server’s IP, not n8n’s.

Hope this helps