Hi Lukas Nöller,
Thanks for reaching out to Microsoft Q&A.
This can be related to your subscription deactivation. Can you please try to reactivate revision and see if it works
az containerapp revision activate --revision <REVISION_NAME> --resource-group <RESOURCE_GROUP_NAME>
Doc for reference: https://learn.microsoft.com/en-us/azure/container-apps/revisions-manage?tabs=bash
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