Blue Box from Hell on A15

[A15 Life Matter]

I have a blue box around the screen of my phone, it is irritating and wasn't a problem until now it doesn't let me selesct anything inside o the box...or....it doesn't go long enough so everything doesn't outside the box didn't for awhile.  I can't stand it and don't know where it came from.  Please tell me I'm not alone and that someone figured out how to fix it.

[BandOfBrothers]

Hello @A15 Life Matter and may I extend a Warm Welcome to the Samsung Community Forum Section for Uk and Eu Members 👋 

Are you able to take a photo of your screen and upload it here , so that the Members can 👀 What you are experiencing  ?

If you perform a forum search you may find existing threads with some further help or guidence within.  

Just to add a good starting point is to double check all your settings, and if you've downloaded a recent app that could be causing this then try Safe Mode  > https://www.samsung.com/uk/support/mobile-devices/how-to-start-my-galaxy-device-in-safe-mode/ turns off downloaded apps and themes etc which may highlight an app or theme that's causing conflict. Alternatively long press the power off button and then long hold on Turn Off to get to Safe Mode. 

Also try Clear Cache Files from the phone's System Partition Section  > https://www.samsung.com/uk/support/mobile-devices/how-do-i-clear-the-cache-on-my-device/ You may need to insert your earphones or hook upto a powered On Laptop or use a Tv's USB Port to access the Clear Partition Section. This may help with lag or stutters as this clears the phone of old/unused or broken cache files.There is also a Repair Apps option in the Menu System too { Possibly excluding the s²⁴ Series of phone's } 

If i can be of any further help please don't hesitate to ask  😎 

[ukraina2]

Have you got the magnifier switched on? That shows as a blue box.

To switch it off go into Settings > Accessability > Vision Enhancements > Magnification.