Phone keeps turning off

[Patio]

Hi I have the S21 ultra 5g in the UK and it keeps turning off or just restarting randomly could any help as to why this keeps happening.  Looking at Google it seems a very common fault.

Help.please.

Patio.

[GoanGeek]

Have got ' Auto optimise daily On' ?
Or might be a rogue app.

I would try a wipe cache and optimise apps when in that same mode.

[BandOfBrothers]

Try some troubleshooting tips such as safe Mode @Patio 

Put the phone in Safe Mode which disables your downloaded app's but let's your stock app's keep working. If the issues stop then this highlights a downloaded app as the possible issue. Come out of Safe Mode and start deleting your most recent downloaded app's one at a time until it stops. https://www.samsung.com/uk/support/mobile-devices/how-to-start-my-galaxy-device-in-safe-mode/ 

A Samsung Experience Store or Samsung Service Centre can take a look at your phone.

If your still within any relevant Cooling Off Period then think about having the phone swapped.

Also if a sim card is glitching this can cause issues. Your network can help you with a sim swap.

One very last resort is a factory reset after backing up.

If you originally set up your phone using a back up to restore your information into the new phone then if you factory reset then set the phone up as new and see what happens just to make sure it's not a corrupted back up causing this.

I wish you all the best with this. 

[Patio]

Thanks I have tried most things except a full factory reset and its still doing it.

[BandOfBrothers]

A factory reset would be your last resort @Patio but may help.

As I said in my earlier reply use a Samsung Experience Store or Samsung Service Centre who can take a look.

They would however ask if you've performed a factory reset.

[AndrewL]

@Patio: How did you get on in Safe Mode? Did the phone continue to restart? 

[Patio]

Hi Andrew that's one I have not tried yet. I did try to do it but I couldn't do it properly. My phone sometimes just turn off for no reason but mostly it happens when charging. We are away a lot in our camper van so charging off 12v. I have two types of chargers both being the new Q3.0 any help would be appreciated. Thanks.

[Patio]

Phone still turning off when not charging now.🥺

[Patio]

I have now done a full factory reset watch this space.

[RanaRauf]

I'm also getting same issue. Had to contact the provider and they will be sending me the replacement phone. For the first time, I tried to get out of the Apple ecosystem and it was very unpleasant. The brand new S21 failed within first month of use. Never had this kind of issue with Apple for over a decade. I'm really disappointed.