Can you provide a little more detail? Is the lag a new development or an ongoing issue? If you recently received the One UI 7 update, did you clear device cache?
How to clear device cache:
1) Turn off your device.
[Your device may need to be connected to a powered USB device (ex: computer) before proceeding to the next step.]
2) Press and hold the Volume Up button and the Side/Power button until you feel a vibration and the Samsung logo appears. Let go of the buttons.
3) You will now be in Android recovery. Use the Volume buttons to highlight "Wipe cache partition."
4) Press the Side/Power button to execute.
5) Use the Volume buttons to highlight "Yes."
6) Press the Side/Power button to execute.
7) "Reboot system now" will already be highlighted. Press the Side/Power button to execute.
