Resolving PS4 Lag issues
Step1 :
Charge your PS4 controller, Low battery is usually a major reason for PS4 lag issues
Step 2:
Make sure to connect yuor PS4 using a USB cable for 20 minutes and now try switching back to wireless mode.
Step 3:
Make sure there are no obstacles between the PS4 console and where your sitting.
Step 4:
Reset the controller by pressing reset button for 3 seconds, use a pencil or a push pin to reach reset button.
Step5:
Make sure there is no accumulation of dust which is causng friction, you can use a vaccume cleaner or air duster to remove any accumulated dust.
Sstep 6:
if none of the above works you can always buy a new controller.