A 403 Forbidden error when accessing the Shiprocket token API typically means your request was authenticated but the user does not have permission to access the resource. check with shiprocket team.

one suggesstion,

The Shiprocket API authentication token is valid for 10 days from the time of generation. After obtaining the token, it should be securely stored in a database or in-memory cache and reused for subsequent API requests. When the token expires, a new token must be generated and stored accordingly for continued access.

Happy coding !!