Hi @Rainbow-8963
Welcome to our forum!
To delete an add-in within your organization, you may take the following steps:
More information: Manage add-ins in the admin center - Microsoft 365 admin | Microsoft Learn
Sometimes, organizational policies set by your admin can restrict the addition or removal of add-ins. Check with your IT admin to ensure there are no new policies affecting add-ins. More: Troubleshoot user errors with Office Add-ins - Office Add-ins | Microsoft Learn
Hope it helps!
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