Sounds like you'll need the account admins to reset the account so a new QR code can be generated with which you can relink the authentication device to your account.
If you are the admin then you can reach out to 365 global customer service here.
https://support.microsoft.com/en-gb/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2
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