Issue: NetSuite OAuth2 M2M authentication is failing with ⁠ invalid_client ⁠ error despite successful JWT generation.

AI generated answer (using internal Slack threads):

Based on the conversations, the issue of NetSuite OAuth2 M2M authentication failing with an

invalid_client

error despite successful JWT generation could be due to several reasons: 1. Incorrect Setup: Ensure that you have correctly set up the "OAuth 2.0 Client Credentials (M2M) Setup" in NetSuite. This includes creating a mapping for the client credentials flow. You can follow the instructions provided in the NetSuite manual or refer to this [video tutorial]() for a step-by-step guide. 2. Assertion Framework Extension: NetSuite uses the assertion framework extension, which makes it more complicated than normal client credentials. A generic service that supports client credentials might not work with NetSuite. 3. Algorithm Deprecation: NetSuite is deprecating the RSA algorithm for OAuth2.0 generation and will use RSA-PSS. Ensure that your JWTs are being generated using the correct algorithm. 4. Token Expiry: The refresh token obtained through OAuth 2.0 is only valid for 7 days. After that, you need to repeat the process to get a new token. This is a manual process and needs to be done every week. You can automate this process to avoid manual intervention. ****** Disclaimer: This response was generated by an artificial intelligence assistant based on previous conversations from multiple Slack channels, and may contain inaccuracies or mistakes. ******