Hello @Ian and Ollie Le Prevost - Resolution IT ,
Welcome to Microsoft Q&A Platform. Thank you for reaching out & hope you are doing well.
I understand that you are unable to grant admin consent for Azure VPN and getting the following error "AADSTS650054".
After checking internally, I discovered that this issue was reported by some other customers, and the Azure VPN Product Group team was involved in further investigation.
The Product Group team found that it was due to a code/configuration change during the recent security fix on the backend. The PG team has reverted the configuration change now and it should not be an issue anymore.
Could you please try again and let me know if the issue persists?
Kindly let us know if the above helps or you need further assistance on this issue.
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