Backend integration

Hello, I started to integrate App Store Server Notifications and App Store Server API, both sandbox, on backend and I have encountered the following problems:

App Store Server Notifications: After a payment is done on mobile, apple sends a notification to our backend which contains a JWT, the problem is that JWT seems to be incomplete and I can't decode it to see the details.

App Store Server API: After a payment is done on mobile, mobile sends to our backend the transaction id, we use that id to make a request to App Store Server API in order to receive details about the transaction, but again the JWT received seems to be incomplete having at the end 3 dots.

Any idea why both of them are incomplete?

Backend integration
 
 
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