yellowish border

[tony4320]

hi everyone i have got a Samsung a21s I've had it since December last year I've had the phone on dark mode for most of the time but last week i turned dark mode off and I noticed there was a yellowish border round the edge of the screen i haven't dropped the phone or damaged the screen the blue light filter is turned off if i take a screen shot the yellowish border is visible on dark mode its not visible either any ideas as to what has happened 

[AndrewL]

@tony4320: Please can you try heading to Settings > Display > Screen Mode > Vivid, then adjust the White Balance via the slider at the bottom of the screen to see if this helps? Furthermore, head to Settings > Accessibility > Visibility Enhancements > Colour Correction, and set this to 'Off' if applicable. It's also worth increasing your screen brightness to see if you notice an improvement. 

If the issue persists, open the Phone app, dial *#0*# into the keypad and select Red, Green and Blue from the series of options. Is the yellow border visible in any of these tests? 

[tony4320]

in the display there is no screen mode setting the colour correction is off and I've done a screen test and the yellowish border is not visible on the red green and blue screens