Laravel PayPal Gateway Issue Fix

I'm experiencing an issue with my Laravel project's PayPal gateway when attempting live transactions, despite using correct live credentials.

Key Points:
- This is an issue isolated to live transactions; sandbox transactions are successful.
- The PayPal payment option for live transactions has been enabled in the project settings.
- Server environment is correctly configured to allow external API calls.
- The issue seems to be related to the live credentials being used.

Im getting this error on live "Authentication failed due to invalid authentication credentials or a missing Authorization header."

I need a Laravel developer who has extensive experience with PayPal API integration, specifically in Laravel projects. The ideal candidate should be able to:
- Diagnose the issue and pinpoint the root cause.
- Implement the necessary changes to ensure live transactions with PayPal are successful.
- Test thoroughly to ensure the issue is fully resolved.

Please only apply if you have prior experience with similar issues and can demonstrate successful resolution.