Hi Zubair Ali,

The error message "Payment Processing Failed - 'The access token is invalid'" indicates that there is an issue with the access token used for authentication when processing the payment with the Tamara payment gateway.

To troubleshoot and resolve this issue, here are some steps you can take:

1. Verify Tamara Configuration: Ensure that the Tamara payment gateway is configured correctly in your Odoo instance. Double-check the configuration settings, including the API keys and other credentials required for authentication.
2. Check Access Token: Verify that the access token being used for authentication is valid and has the necessary permissions to process payments. If the access token has expired or is incorrect, you may need to regenerate it and update the configuration accordingly.
3. Debugging: Enable debug mode in Odoo and check the logs for any errors or warning messages related to the payment processing with the Tamara gateway. This can provide more insights into what might be causing the issue.
4. Test in Sandbox Environment: If Tamara provides a sandbox or test environment, try testing the payment process using the sandbox credentials to isolate whether the issue is specific to the production environment or configuration.

By following these steps, you should be able to diagnose and resolve the issue with the access token invalid error when processing payments with the Tamara payment gateway in Odoo.

Hope it helps