My elderly neighbour is having this problem every time he switches on his Pro TV box. I registered him with ITV quite a while ago and when I go round to check he is still logged into ITV X. The problem seems to disappear after I go into to ITV X but I’ve told him that this should not be happening and that he hasn’t done anything wrong.
The first step is always going to be to try a factory reset (assuming you've already tried turning the power off and on again).
Thanks. I will try that when I next see him.