Old phone number linked to Google

So when we switched to T-Mobile from AT&T, we wife had to change her number. Unfortunately, my wifes old phone number was tied to her Google account, and now we can't get into the Google account because Google keeps wanting to text a code to her old phone number. I'm sure the old phone number belongs to someone else now, but maybe T-Mobile can somehow intercept the code for me, or some other way they can help? Thanks in advance for any help or info.