ISE10 possible controller problem

We have a 14 year old ISE10, WM25.3 model 1606W. It has been fab. Now, it is not responding properly to commands. We tried a reset, and it worked perfectly for one wash, but at the end it didn’t show END above the start button as usual. Since then it has refused to let us change the wash, and is stuck on a 60deg White wash (one I never use) and can’t be changed. It is not showing any fault codes.

We assume, as it is capable of washing fine, that there is an issue with the control board, but how do we confirm that? I can see, from other threads, that a controller is an expensive item, and clearly we would need to get the right one, if it is the problem. How do we ensure we are getting the right one? And as the company has gone bust, is it possible to even get spares? Any help gratefully received, as we are reluctant to chuck out a lovely machine.