touchscreen problem in some areas

[dgops]

im using this phone 3.8 years. now im facing a problem of  touchscreen in some areas is not working what is the resone. my phone is not goes water damage or scrached etc. i'm a sony lover pls tell me how to solve or fix problem. now i bought xperia z3

[MarlonUk1]

try to boot to safe mode..

does the problem exist?

 also you can try to perform software repair using Xperia Companion

if the problem is still present it most likely to be a hardware problem. have your phone checked at your local service center Local support