Go to terminal under the server and edit /etc/cl.selector/php.conf

Add the following lines at the end of file 

Directive = date.timezone
Default   = Asia/Kabul
Type      = value
Comment   = Change Timezone.

I have used Default Asia/Kabul as i am using Kabul, Afghanistan time, once you add these lines than go to domains cPanel > File Manager > .cl.selector > Open the desired php version file with editor > add the following line 

date.timezone = Asia/Kabul 

Save and exit.