@Shea Martin
Thank you for your post!
Can you try to have your co-admin close out of all their browsers and retry the operation?
- If closing out of the browser isn't possible you might be able to go into private browsing, log-in again, and retry the operation.
If the above fails, you can definitely assign the Contributor RBAC role to your Co-Admin (at either the subscription or resource group level) since the contributor role grants full access to manage all resources. For more info.
If you have any other questions or are still running into issues deleting your resource groups, please let me know.
Thank you for your time and patience throughout this issue.
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