So are you asking about the fork in the bike, which it sounds like you knew the answer to, or the hub in the fork? If it has a 9mm axle, that doesn't work with thru axles. Joytech is a large company with many types of hubs. It is possible that your hub is the kind that can be adapted from quick release to thru axle by changing the hub end caps with Joytech factory parts. But without knowing what model hub it is or if those end caps are available, no one is going to be able to advise you.