Hello @Melanie Barham,
Apologies for the delay in fixing this.
The issue relates to a tenant lockout situation where no other global admin in the tenant has the necessary admin rights to re-register MFA.
To resolve this, we engaged our Data Protection team through a support ticket. As per the update on support case I see this has been resolved. Let me know if you need any further assistance.
I hope this information is helpful. Please feel free to reach out if you have any further questions.
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