I noticed mine was doing the same thing. I would get it adjusted and the next day it was down about two inches. The last time I adjusted it. I pulled up hard on the handle and it has stayed up.
I picked up my FITS kit today at the dealership. No one knew what FITS kit was. After I told them what it was and showed them a picture. We went looking for them. In a back storage room we found about 10 of them.