My sewing machine was working well, then the tension went all weird. I have threaded, rethreaded and rethreaded again. I have put in a different threads and different bobbins. I have also changed the needle, have changed the tension at least 20 times and I still can not get the tension back to normal. Any and all suggestions are welcomed. Thanks in advance for any help, I am ready to pull my hair out.

Did you clean out the bobbin area of lint, that can really affect tension as well. Or maybe a new needle.

I've had similar problems and thoroughly cleaning the bobbin area helped.

What kind of thread are you using on the top and in the bobbin?

Are you getting loops on the top or the bottom?

Make sure there isn't a piece of lint behind the Thread Tension Dial, and that the thred is feeding properly through the Take-up Lever. Check also to see if a small piece of lint is trapped in the bobbin case where the thread feeds out. Back the tension off slowly until you reach 0, then slowly bring it back until your Auto-Tension Light comes on. Then you can start adjusting from there very slowly.

Make sure the needle is in correctly. I know this sounds like it would be a given. But I have one of these machines and it greatly matters. And that the thread is going through them correctly. But I went through much drama of breaking thread, all kinds of issues on a new quilt i had started. And I couldn't understand it since it had done so well on the one I had just finished. Turned out. I needed a different needle size for the fabric I was currently working on. Was sooooo glad to get it resolved.lol Good luck

The thread winding from the wrong direction matters a lot. I just pick up the spool and set it on the other end and try that.
Lint can get so far down under there. When you think all the lint is out there can be more.

I have changed the needle 4 times now, put in a different spool of thread, going the correct way. Cleaned the bobbin area again and still no luck. Do I need to bring it in for service? I just got it out of service.

I don't have a auto tension light. But it does look like it should be between 4 & 5.

was it working correctly when you first got it out of service?
Depending on how long you have had it back and how much you have used it since servicing, I would contact that person and ask them? Maybe something they did or didn't do!