remove tenant, to move domains to another tenant

[natallia888]

I can no longer access tenants, which I previously created myself. so I can't install my mails with current tenant now. I get message that username is not valid, in both cases. I can only get support from company where I bought office, they refer me to microsoft. microsoft refers me to company that sold office. a vicious circle. how can I arrange it?

[#2]

If the tenants are still active, you can request Microsoft to reset your user's credentials and gain access. Alternatively, you can use the domain takeover process: https://learn.microsoft.com/en-us/azure/active-directory/enterprise-users/domains-admin-takeover