@Vladimír MATOUŠEK Thanks for reaching out.
For your scenario, you will need to contact our MS support team using the numbers provided here :
https://support.microsoft.com/en-us/topic/global-customer-service-phone-numbers-c0389ade-5640-e588-8b0e-28de8afeb3f2
The support team will then verify your identity and once the verification is done, they will help you unblock the tenant.
For future purpose after this issue is resolved do have some emergency access plan. Please read more about how you can create one here : https://learn.microsoft.com/en-us/azure/active-directory/roles/security-emergency-access
Let me know if you need any further help on this.
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