Based on your description, I understand that you are locked out of a unique global administrator account and that password recovery is not configured.
As the processing of account-related issues may involve personal information, in order to protect your privacy, you can reach out to 365 global customer service here Global Customer Service phone numbers - Microsoft Support
You can still get help from the following documentation Get support - Microsoft 365 admin | Microsoft Learn
Once you have resolved the issue, it is recommended that you create additional administrator accounts with recovery options.
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