Have a galaxy tab s7 & cannot remember the pin. Am trying to do a factory reset but it won't power off. Tried the power button, volume up/down button  at the same time repeatedly. When it works, goes to power off screen, tap it to power off & it goes right back to the screen for the pin. Checked the user manual, did a goggle search, checked youtube, checked this community for previous posts/answers.  Nothing works. Been at this for 4 hours to no avail. Any ideas/suggestions would be really appreciated!!