Turned off the water supply before applying any wrench and screwdriver.
Remove decorative parts of the knobs. Underneath each knob, there will be a screw, remove it with a screwdriver.
Use the wrench to loosen and remove the packing nut. Check the removed part for any damage.
Also, inspect the O-ring and washer inside the valve seat.
Remove the washer and put the replacement inside the seat.
Now reassemble all the parts and check to see if you have licked that leak.