Issues logging in to FC Companion

Hi All, I'm a 41 year old dad whose last console I owned was a PS2 with discs and horrible graphics!! I'm looking for some help please. My son has a Xbox S Series with FC25 and an Ultimate Team but no matter what we try he can't log in to the FC 25 Companion App on his iPhone, the error we get is: "It looks like your EA Account doesn't have A Football Ultimate Team 25 Club. Before we keep going, make sure you're logged in with the right account. In order to use the FC 25 Companion App or Web App, you will need to create an Ultimate Team 25 Club on your console or PC".

He already has an Ultimate Team and we are able to log in to his FC 25 account and EA account without any issues. We are going away for the weekend and he wants to play FC 25 on his phone, he tells me he needs FC 25 Companion but we are having issues with it.

I tried searching on Google for a solution but nothing works. If anyone is able to help I'd be very grateful.

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