iphone 6s plus screen is glitching out - typing random things and opening random apps and unable to control the screen

My phone started glitching out today for no apparent reason. It opens random apps, calls people and starts typing messages, and I have no control of the screen. I've had it for over 2 years and it's never had any problems. I've never changed the screen and it's never been damaged in any way.

I reset the phone twice, updated it, and I've cleaned the screen properly but nothing worked. The only thing that has helped is bending my phone but that only works for a few minutes and then I have to do it again.

Does anyone know what's causing this and how to fix it?

Is it something that apple can fix? And is it worth fixing it or should I just get a new phone?

I've read about a lot of people having this problem but there doesn't seem to be any fix for it so I'd love some help if you know what to do! And I'd appreciate if Apple could comment on this.