My Cobra Class 4 has developed a serious issue. It stitches for about 10-15 stitches then locks up. I have to back up manually, then it will go again until it locks up. The bobbin holder is very loose, so many that’s the culprit? I’m at a loss and I don’t know where to turn. I’ve been searching for someone in my area who may be able to evaluate and repair, but no luck. Has anyone else had this issue? The photo below is what it looks like when locked. Thank I’m advance for any help!