New account issues.

Hello. I live in Troy Mi and recently moved 5 phones and 6 other devices from AT&T to Xfinity Mobile. When discussing this change with the salesperson on West Maple in Troy, I mentioned that one of the phones being ported was used by my daughter, who currently resides in Bratislava Slovakia. I asked if that was an issue with the port and was assured by this salesperson that it was not. Well, it’s going on 2 weeks now since the port took place. This sales person who promised a smooth transition initially couldn’t get the eSIM to download at all onto her phone.  One of the other reps at the store finally stepped in in his absence and sent a QR code to a roommate which she used to download an eSIM.  That eSIM gave her back her phone number and she is now able to make calls and send messages over WiFi. She still is unable to connect to a tower in Bratislava and has zero cell or messaging capability away from WiFi. The salesperson who promised us this was not an issue has completely ghosted us and the calls to the helpline have not helped to resolve the issue.  We are at the point where we don’t know what to do. The salesperson no longer answers texts from me and she has no phone service away from WIFI. This is the worst customer service I have ever experienced. I’m now sorry I changed from AT&T due to the stress of her being regularly out of contact with us. Can someone please HELP?