Sure it's repairable and adjustable.
First, welcome!
Second, why do you think it is slipping. Tell us the story. Is is something you would have normally been cutting fine, now it's slipping all the time. Is it new to you and doing this right off the bat? etc.
Third, it's covered in the manual for the MX6 on how to adjust it. Link below. OMW49246: MX5, MX6 and MX7 Rotary Cutters table of contents