Japan Post Bank Account: Does Japan Phone Number Necessary.

Last week, I opened a bookbank-less account via the Japan Post Application. I remember there was a field for a phone number. Since I do not have a Japanese phone number, I ended up writing down my Thai phone number (from my home country). Today, I received the cash card. When I tried to connect the cash card to the Yucho Bankbook App, I entered my card number, my name in katakana, and my PIN. However, before reaching the OTP number stage, I encountered an error indicating that my phone number is invalid.

My question is: if I go to the JP Bank office and try to fix the phone number issue, is it possible to use my Thai phone number since I don't have a Japanese phone number? What should I do?