Galaxy Note 9: Why do some areas of the touchscreen are not responding properly?
If you attach a screen protector or optional accessories to the touchscreen, the touchscreen may not function properly. Especially, some Samsung-unapproved protector glasses or films only have tapes on the side edges. When you attach such products to the device, protector film or glass may not be in perfect contact with device and may get loose from device's screen.
This causes that some areas of touchscreen may not recognize touch actions and won't respond. We recommend to use only Samsung-approved accessories. The usage of unapproved accessories may cause the performance problems and malfunctions that are not covered by the warranty.
Additionally, please check the below options:
• If you are wearing gloves or if your hands are not clean while touching the touchscreen, or if you tap the screen sharp objects or your fingertips, the touchscreen may not respond or has an issue.
• 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 you are still having trouble with touchscreen responds even though detaching a screen protector or optional accessories from the touchscreen, please contact a Samsung Service Centre for Mobile phones.