iPhone X clicking on its own

Try a forced restart of your iphone:

• On an iPhone X, iPhone 8, or iPhone 8 Plus: Press and quickly release the Volume Up button. Press and quickly release the Volume Down button. Then, press and hold the Side button until you see the Apple logo.
• On an iPhone 7 or iPhone 7 Plus: Press and hold both the Side and Volume Down buttons for at least 10 seconds, until you see the Apple logo.
• On an iPhone 6s and earlier, iPad, or iPod touch: Press and hold both the Home and the Top (or Side) buttons for at least 10 seconds, until you see the Apple logo.

Regards

Giulio

If you have performed the troubleshooting steps that ProustGiulio has provided and are still experiencing problems with the touchscreen, then make a Genius Bar appointment at the nearest Apple Store. It would seem that the digitizer for the phone is failing. This can cause these issues with screen presses.

If the issue still persists, you can follow another basic troubleshooting step, restoring your device to factory settings and installing a fresh copy of the current iOS (11.2.6).

To perform this operation, make a full backup of your iPhone's content, then read this support guide, and at the end set up your iphone as new:

Restore your iPhone, iPad, or iPod to factory settings - Apple Support

Then restore the iphone from the previous backup:

Restore your iPhone, iPad, or iPod touch from a backup - Apple Support

Regards

Giulio

Thanks Giulio, I switched it off for 2 hrs, started it back, it asked me to upgrade to 11.2.6 and the phone seem to be ok after the upgrade.

Finally, gave it back and got replaced with another one

Have an update. Looks like I spoke too soon.

Problem remains even in 11.2.6

Spoke to Apple support last night, they took me through the restore process and it didn't fix the problem either. So now have an appointment booked with Genius bar for Thursday.

I am left with a ghost iPhone x for the next 4 days :-(

Thanks for the steps to restart, but why is this happening and how do we stop it?

I have tried restarting and this this keeps happening and making the phone unusable.

Thanks for the steps to restart, but why is this happening and how do we stop it?

How much available storage space is there on your phone? A lack of storage can cause these issues.

Update: Went to the store where I was given the appointment, only to find that they don't do genius bar appointments :-(

Back with apple chat support to find a store who can investigate the issue. Now looks like I have to wait for another week before they can see me in Birmingham store.

I feel NHS wait times seem to be better than getting an genius bar appointment.

Slowly, I am starting to loose trust in apple.

Hi Thanks for the reply. The phone currently have 165.45 GB free

You’re welcome, maddy

Thanks Chris, I will book the appointment if the problem remains even on 11.2.6

Sorry about that, Maddy.

After your appointment next Thursday, please keep me informed.

Thanks and regards.

Giulio