Hello Thomas Kallenberg
Thank you so much for your patience while working on this request.
Following our discussion, you were unable to approve the private endpoint connection for the Azure PostgreSQL flexible server across the tenants.
Kindly I request you to please follow the below steps for cross tenant private endpoint approval.
Step1: Please verify whether the resource providers Microsoft.network and Microsoft.dbforpostgresql are registered in both the subscriptions.
Step2: If not registered, please try to register it.
Step3: Once the resource providers are registered, please try to approve the private endpoint connection which is in pending state.
I hope this has been helpful!
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