Unable to log in to authenticator.

I have recently changed my mobile phone, and I'm trying to access the authenticator app. However, I'm unable to do so as I appear to be stuck in a login loop.

When I attempt to log in, I'm asked to confirm a two-digit code which I cannot do due to having no access to my old mobile phone. I try the alternative login using other email addresses to get codes, it allows me to do this and I reset my password. But when I try to log back in, it does not allow me to use my password and I keep having to get codes which then times out due to doing it too many times per day. What am I doing wrong?