Samsung J1 SM-J120F - Manual (Page 84)

Appendix
84
The touchscreen responds slowly or improperly
• If you attach a screen protector or optional accessories to the touchscreen, the
touchscreen may not function properly.
• If you are wearing gloves, if your hands are not clean while touching the touchscreen,
or if you tap the screen with sharp objects or your fingertips, the touchscreen may
malfunction.
• The touchscreen may malfunction in humid conditions or when exposed to water.
• Restart your device to clear any temporary software bugs.
• Ensure that your device software is updated to the latest version.
• If the touchscreen is scratched or damaged, visit a Samsung Service Centre.
Your device freezes or encounters a fatal error
Try the following solutions. If the problem is still not resolved, contact a Samsung Service
Centre.
Restarting the device
If your device freezes or hangs, you may need to close apps or turn off the device and turn it
on again.
Forcing restart
If your device is frozen and unresponsive, press and hold the Power key and the Volume
Down key simultaneously for more than 7 seconds to restart it.
Resetting the device
If the methods above do not solve your problem, perform a factory data reset.
On the Apps screen, tap
Settings → Backup and reset → Factory data reset → RESET
DEVICE → ERASE EVERYTHING. Before performing the factory data reset, remember to
make backup copies of all important data stored in the device.