Hi I’m gone explain, How to solve touch problem of samsung J701f after update android 9.0.
Now connect mouse with using OTG to the phone and remove google account.
Power off your phone and put the phone in download mode.
Check Swrev version on phone and download same version of android 8.0 from given link https://www.sammobile.com/samsung/firmware/SM-J701F/
After download complete extract firmware and flash with odin.
Wait for complete after complete touch will fine works.
Remember swrev binary version should be same or higher.