My problems like that were the result of a bobbin with the thread going the wrong way.

Couldn't you just flip the bobbin over and the thread would go the right way? Or am I missing something.

Something else to check about the bobbin. A friend of mine had a Brother embroidery machine and a Brother Sewing Machine and the bobbins were very slightly different. They both fit both machines and sometimes they worked fine but sometimes they caused problems, and her life got a lot better when she simply threw away all her bobbins and started out with new ones, marking the sewing ones with a permanent marker.

So if something like that is possible, start with a fresh known to be correct bobbin. Double check your package if you still have it to confirm you have the correct one.

Hopefully it is something very simple and not costly. When all else has failed you are right to take it in for service. Been there and the frustration level just keeps climbing. Take a deep breath.

This would be my first thought. I'd wind another bobbin and try that before I tried anything else.