@Aaron Venson Can you share the screenshot of the error message? When exactly are you getting this error message? How are you trying to delete?
Please try the following steps and let me know the results. Follow this document to find and delete unattached Azure managed and unmanaged disks
https://video2.skills-academy.com/en-us/azure/virtual-machines/windows/find-unattached-disks
When you delete a virtual machine (VM) in Azure, by default, any disks that are attached to the VM aren't deleted. This feature helps to prevent data loss due to the unintentional deletion of VMs. After a VM is deleted, you will continue to pay for unattached disks. This article above shows you how to find and delete any unattached disks and reduce unnecessary costs.
You may also refer to the suggestions mentioned in the blog
Hope this helps!
Kindly let us know if the above helps or you need further assistance on this issue.
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