Hi @Guiqing Wang
Thanks for reaching out to Microsoft Q&A Forum .
Few of the resource provider registrations need backend team approvals .And few of the resource provider registrations take some time and automatically get registered .
Please verify the status of your resource provider if its still stuck , You can try un-register resource provider from CLI and try to register it again.
And if is still stuck like the previous one. Please go ahead and file a support ticket one of the compute engineer will troubleshoot the cause of the failure .
Hope this was helpful .
Thanks,
Pradeep
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