If you are using the live endpoints you will need to ensure that you are using your Live Credentials and not your Sandbox Credentials. The Live Credentials are different than the Sandbox Credentials.
Also if using Rest API and completing Direct Credit Cards, you will need to ensure that you are enabled for Direct Credit Cards.
Here are the steps for obtaining your live Client ID and Client Secret:
Go to https://developer.paypal.com
Click on Log into Dashboard at the top right
Log in using your Live PayPal email and password
Scroll down to your Rest API Application
Click on the Application
Click live at the top right hand side
Paste live Client API and Client Secret into your Rest API Integration.
Thank you,
Jennifer
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