One Time Passcode Security Sucks

My partner and I are currently overseas in Australia. My partner decided to purchase a new Iphone 16 at the Apple Store here in Sydney. She traded her Iphone 13 and transferred all her data/info via iCloud to her new iPhone. The apple store associate said her esim would also get transferred but DID NOT! The iPhone 13 got wiped, now the only way to get an eSim sent OTA or via QR code is through a ONE TIME PASSCODE. How can she get a one time passcode if her sim isn't even on her new phone!? What adds to her frustration is that her email address logged out and she needs her one time passcode from her phone number AND her bank account needs a one time passcode as well. I understand the security measures for a one-time passcode but there should be a bypass method available even when calling it into customer support. I asked the tmobile rep 'So if someone travels overseas and loses their phone, they're pretty much SOL because they cant get a one-time passcode? Pretty much they cant use their phone number until they get back to the States?' .... The Tmobile rep had no response, only the 'I understand your frustration' customer service auto-line.

PS: I even asked if my brother can go to a tmobile store to get a physical sim and he mail it to Australia but because he isn't an authorized user, they need a PASSCODE to add his name.

Do better T-Mobile.