@J van Eerd Firstly, apologies for the delay in responding on this and any inconvenience this issue may have caused. As this issues need more investigation and live troubleshooting for quicker resolution I would recommend you to contact azure support.
If you have a support plan, requesting you to file a support ticket, else please do let us know, we will try and help you get a one-time free technical support.
In this case, could you send an email to AzCommunity[at]Microsoft[dot]com referencing this thread as well as your subscription ID. Please mention "ATTN: Preeti" in the subject line. Thank you for your cooperation on this matter and look forward to your reply.
Hope it helps!!!
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