A hard reset / factory reset is pretty much as deep as you'd want to go with this.
If you've used a firmware that you've downloaded then just double check it's the correct software version please.
If your resetting your phone back up with a previous back up then try not using this and set up the phone as a new device just to see if it's the back up that's causing conflict.
If you can you may also want to use Safe Mode > 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.
Ultimately a Samsung Service Centre can check out the phone for software and hardware problems.
I wish you all the best.
Daily Driver > Samsung Galaxy s²⁵ Ultra 512Gb ~ Titanium Black.
The advice I offer is my own and does not represent Samsung’s position.
I'm here to help. " This is the way. "
