@Rubinetterie 3M Rubinetterie 3M Thank you for reaching out to us. As I understand you want to recover the password of the original Tenant, the password recovery via email is not working as expected, in this case you need to contact our Global Support team - [https://support.microsoft.com/en-us/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2 where the agents will open a case on the affected tenant for you (if there's none already) and ask them to redirect the support case to Data Protection team where you will receive a from them, help you further on tenant recovery process after validation.
Let me know if you have any further questions, feel free to post back.
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