The front knobs need oiling. Take a flashlight and shine it from top to bottom in the front where the knobs do not move. This will be from inside the machine. You will be looking at the back side of the knobs. You will see where the gears connect at the bottom. Oil each one separately and slowly start moving the knobs. They will work loose and be fine. I have had trouble with this issue in the past. You may have to take the bottom off the machine to get to the gear. I like to use a longarm quilting ruler, as it has a long snout on it for oiling tight places. Good luck.