Hi jagadeesevil,
Does this appear in the latest firmware version WW-90.11.162.88?
If yes, could you tell us when the problem appears:
1) What apps you are using when this happens, or what specific actions on the phone cause this lag problem.
2) Which apps are in the background currently.
3) Please try clearing these background apps and check whether the problem is improved after doing this.
Thank you 🙂