iPad photos not updating consistently

My iPad won't update photos properly: any ideas apart from a full wipe and reinstall?

I have a fully functioning photos setup with laptop and iphone. IPad is properly set up with icloud etc. IT updates the occasional photo - like 1 from a recent batch of 140, and none of my past is visible (about 14k on my iphone)

Any dieas about how to force it to sync fully?

All I can think of now is to wipe it and reinstall everything again :/...

Thanks