I started the server and succesfully fetched the data from the server via Rest API with OAuth 2.0 authentication.
After a while I cannot fetch the data anymore, I believe because of "Logoff Web User".
After restarting the server it starts working again.
Maybe it a specific version problem?

2022-05-10 10:53:51 8.5 2021-04-18 (build 85360453)
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2022-05-10 11:04:57 AD Login
2022-05-10 11:04:57 /THREAD(18) FindSlot() from non main thread

2022-05-10 11:04:57 /THREAD(20) FindSlot() from non main thread
2022-05-10 11:04:57 Database not in Live Mode
2022-05-10 11:04:57 Database is in Restricted mode
2022-05-10 11:04:58 /THREAD(21) FindSlot() from non main thread
2022-05-10 11:04:58 /THREAD(19) FindSlot() from non main thread
...
2022-05-10 11:05:58 SYSTEM Logoff Web User