I have a Diamondback Apex with Rockshox xc30 and all I did was turn the knob for the preload adjustment and it suddenly came off. I tried putting it back together but it won't go all the way back in. I try riding it but even the lockout won't hold the crown from slipping all the way down. This makes the hole spring be seen and the handlebars very low. The suspension is now rough and useless. What should I do?