K1 max CFS upgrade error

Hello everyone, I have a K1 Max printer with CFS and I'm having a problem. Printing with a single color works fine. When I try to print multicolor, the filament jams when reverting to CFS. The filament sometimes gets distorted when reverting from the extruder. Printing sometimes goes up to 45%, sometimes up to 20%. Has anyone had the same problem and fixed it?