Hello there,
Thank you for reaching to the forum. Currently, we do not support service accounts, but will take your feedback into consideration into our prioritization planning.
In regards to the
401 UNAUTHENTICATED error, please see our
Common Errors page. Please see the responses to your other questions below.
1. How can I fetch reporting data in the background task?
Based on your implementation, you can call the AdMob API for reporting data at a recurring time interval, however, please follow our
quota limits and
guidance on getting report data efficiently.
2. Is it possible to generate infinite (never expire) access tokens?
It is not possible to generate infinite access tokens. However, a
refresh token allows your application to obtain new access tokens, however, they may expire in the
following circumstances. The AdMob API's
OAuth Playground guide instructs users on how to retrieve their credentials and tokens.
Please do not hesitate to reach out if you have any additional questions.

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