How can we extend/resize the LVM partition online which has snapshot enabled?

Issue

• Extend snapshot enabled filesystem.
• One of the server having snapshot enabled volumes, we want to increase the snapshot enabled filesystem /data.
• We would like to know the procedure to increase snapshot enabled filesystem, also want to know how much space to consider for snapshot.
• When trying to extend the logical volume (LV) I see the error:

# lvextend -L +20G /dev/test_vg/test_lv
Snapshot origin volumes can be resized only while inactive: try lvchange -an.