The only other way is to try via email if you look at the bottom of the box you will see it’s says try by email or help option hopefully you still have access to that email and you can verify that way
the problem is 2 step authentication is not even set up yet but in order to set it up it needs to verify using the last registered number and so it’s a loop in their system
I’ve been on the phone to them for a couple hours and they finally said you will need to contact your old phone service provider as there is nothing they can do their side
so they them selves did not find the fix I did which is there is another option to verify via email