Bernette B79
Please help!!!
I just got Bernette B79. I tried my first embroidery and everything went fine. then started another and it went absolutely wrong. the lower thread came on the surface and the upper thread was on the back of the fabric. Then machine went crazy, I could stop it only turning it off. My embroidery stuck as the main thread were in the needle plate. I cleaned bobbin compartment, changed needle, was trying different tensions for the upper thread, but unsuccessful. Please help me to solve this problem.