I used to have the same problem before. I think you can't get your account back. Btw why'd you loose your phone number? Next time be more cautious. I suggest you just create another xapo account if amount of bitcoins is not that higj but if it's worth to get all the troubles of waiting for support to reply then you can contact support over again until they replied to you. Explain why you loose the access to your 2fa.
Using prepaid phone
Thats why Plus the xapo app got problem. Reinstalled and need phone number and 2fa again.