You may have to loosen the upper triple clamp bolts. And it may help to apply heat, but relieve the air pressure & drain the oil and do this with the forks off the motorcycle.
The fork caps thread into the fork tubes. The fork cover ears fit over the fork tubes. The air valve assy fits over small holes in the fork tubes and there are gaskets & o-rings to seal the air valve assy. see diagrams at Partzilla. eebbaayy photos are helpful for stuff like this >> search the part numbers or use other searches, such as ZN700 forks.
My fork caps were stuck, so I removed the forks from the motorcycle & applied heat using a propane torch. To remove them I had a spare triple to use as a clamping device. Otherwise, you may have to re-install the forks to remove the caps, but don't tighten the upper clamp bolts.