1. Try optimising your device. Go to Settings > Device Care > Optimise Now
2. Check for any other software updates
3. The issue might be a 3rd party application installed in your phone. You can do a Safe reboot. Hold the Power button. Touch and hold the Power off button until Safe Mode icon is displayed. Tap Safe Mode. If you have entered Safe Mode, this will show at the bottom of the screen. If your phone works fine, uninstall the apps that were downloaded or updated before the issue began. After doing this, you can restart your phone to get out of Safe mode.
If the issue still exists, you can visit your nearest Samsung Centre.