iPhone sometimes becomes unusable - trying to open all apps/glitchy/move from side to side

Since last 5 days ago my daughter's iPhone XR sometimes becomes unusable, tries to open all apps, glitches by trying to swipe up constantly, and move from side to side. Makes it impossible to use, even when it's locked it moves about like someone is swiping on the screen. Then it becomes fine for a while (a few hours), but now seems worse.

version is 17.4.1 21e236 (not sure when it updated)

Restarted plenty of times, seems worse when starting up.

We've removed the screen protector in case it was that.

Any ideas? Happened to anyone else?

thanks