viewport zooming all in paperspace

Hi, i have 3 viewports in paperspace, when i click one of them it's zooming extent all the 3 viewports. There might be a system variable might have changed for viewport or zoom. Any idea? please help.

If I understand your question right it seems you have the viewport locked. While in paperspace, select the viewport and then bring up the properties for it. Down near the bottom in the Misc section, you will find the Display Locked. Set this to No. You will then need to click inside the viewport to be in modelspace to then zoom inside of the viewport.

It's the UCSFOLLOW variable that you need to change.

This variable is set independently for each viewport, so you will have to double click inside each viewport and reset the variable to 0.