Top thread winding around bobbing
I have a PE-150. I took it for service in Oct. for a tune up. I haven't used it since. I am trying to make name tags. The sample that came back with the machine stitced fine. Every time I start stitching on the name tag, the top thread winds around the bobin, making a huge birds nest mess in the bobin case. Help! Can someone tell me what to do to fix this? I have tried changing tension, and it isn't helping.I've gone down to 3 and up to 8 on the tension dial. Doesn't make a differnce. The machine is threaded right. I don't know what else to do.
Thanks for any help