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For this we need an exact error code for the backup failure. Because there are various reasons to encounter the RP collection failures.
Please refer to the below doc, there we can find many reasons for restore point collection failure.
Refer below document: -
Troubleshoot restore point failures - Azure Virtual Machines | Microsoft Learn
Hence, please specify the error code which refers to the failure.
Please let me know how it goes, we will always help as you needed.!
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