Sooner or later seals leak. Replacing it is not hard but does require some special tools and some mechanical experience.
But that’s not a bad leak. Before doing anything try the old milk carton fix trick.
That outer seal is just a dust scraper. Take a screw driver and carefully pry it loose and slide it down out of the way. Then take a milk carton and cut a piece about 4” long and 2” wide. Carefully slide it up between the seal and fork leg and work it around and up and down. Sometimes just a piece of dirt gets in the seal and causes the leak. If you’re lucky this will fix it. Nothing to loose and really does help sometimes.
I replaced the seal with a Suzuki one.
for the oil I was told by Ohlins 170mm from top no spring or spacer.I used an old spray bottle , cut the tube to 170mm and sprayed into a bottle.
can and one tell me how to reset the fork settings?