A Microsoft file hosting and synchronization service.
Hello Michael McGrath
Thank you for posting question to Microsoft Q&A Forum.
As I am forum moderator - who does not have access to internal system to check this for you. Since OneDrive and SharePoint are related in Microsoft 365, getting an error message while trying to access SharePoint would also return the same result while trying to access OneDrive.
You might need to raise a ticket to Microsoft Support Team in Microsoft 365 Admin Center via this link (Could be only accessed if you are global administrator of the organization).
Reference: https://learn.microsoft.com/en-us/troubleshoot/sharepoint/sites/page-blocked-violates-acceptable-use-policy
I hope the information is helpful. Please let me know once you have any updates after contacting Microsoft Support Team and you'd like to share it with us.
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