Screen time out not working

[SelinaH]

Just bought the samsung s10 and the screen does not time out naturally. Ive set it to 15 seconds and it doesnt time off unless i manually lock it. 

[SjorsK]

Is it during watching something like a movie? Its possible for devs to disable this option for specefic apps.

That said, if it doesn't work on the homescreen I would recommend to simply reboot the phone and try again