How to regain access to Microsoft business account when MS Authenticator doesn't work

How to regain access to Microsoft business account when MS Authenticator doesn't work (device change, backup doesn't work) and I'm an administrator. Dual authentication was only set up for Authenticator applications. And now it asks me to enter the verification code from Authenticator and there I am unable to log in (because it also asks for the verification code from Authenticator).