Hi Olle Carlberg,
Thank you for reaching out to us on the Microsoft Q&A forum.
Based on the query provided, we understood that requests for ACR Tasks pertaining to the container registry and specific subscription IDs are currently not permitted.
Please note that if you are utilizing an Azure free trial subscription, we recommend transitioning to a pay-as-you-go model. ACR is temporarily suspending ACR task runs funded by Azure free credits.
We have conducted tests on our end and have successfully executed the "az acr build" command within a pay-as-you-go subscription. Attached below are the screenshots for your reference.
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