There are some fixes you might try to see if any of them work for your phone. Those are the following listed below:

• Make sure your touch screen protector doesn’t interfere with proper operation.
• Make sure there’s no internal/external damage (cracking or shattering glass)
• Disconnect your USB-lightning port to check if it works.
• If your phone is above normal temperature wait for it to cool down and then try again.
• Restart your device.

If none of the fixes above work for you, you might need to get your iPhone checked by professional technicians. Here at ifixit bd, we have dedicated and experienced technicians who specialize in repairing and resolving issues regarding touch on your iPhone 6 Plus. ifixit bd is located in 4 different service points. Which are in convenient locations for you around Dhaka, Bangladesh.