Question: MM Newbie: truss rod wheel is hardly moving

Hi everybody!
I bought a used Bongo 6 (built2009)
Its my first MM so i have no experience with the trussrod wheel.
I tried to move it a litte, just to get shure it works.
I need a lot of strength to move it just 2 mm.
I used a “allen key” for this.
With all my other basses (Warwick, fender) i needed less strength (but with the specific tools)

Is it possible, that the wheel is stuck?
any Ideas?
P.S I read the thread with the vaseline……no i won´t do that!

thanks in advance
Gerald