As the word speaks Keep screen on while viewing feature doesn't work at all as per screen time out 30 seconds even though I'm viewing mobile it dims and locks screen after 30 seconds ...
As per your concern, we would request you to kindly perform the following steps to set the display timeout option.
Settings > Display> Screen timeout> Tap on your preferred Screen timeout> Select new screen timeout.
If the issue persists, kindly report the problems with a log file. To share a log file, click on the Samsung Members Application (Open Samsung Members Application > Support> Tap on send feedback> Choose Composer> Select error report> select the appropriate issue category> Type your query and send).
