Embroidery sewing machine stopped working

Where is the thread bunching up?Make sure you have the correct thread for the needle size and material. Make sure that the thread is not old and that the needle is not bent. also, check the top tension in relation to the material being used. You could clean out the feed dogs in case there is lint jammed in there too. :)

Sounds like bird nesting.
The #1 thing is to install a brand new needle (old, worn, nicked, or bent needles can create a lot of havoc).

Remove all the thread from the machine. RAISE the presser foot and rethread from the beginning verifying that it is threaded correctly. Make sure the bobbin is loaded and threaded in the bobbin case properly.

WHY IS THREAD BUNCHING UNDERNEATH MY FABRIC

Why Do Get Bunched Up Thread Under My Fabric

8 Tips to Fix Birdnesting in Embroidery
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Be sure to RAISE the presser foot BEFORE threading the upper thread. (Remove the upper thread and rethread from the beginning.) Upper thread malfunctions commonly occur if it is not threaded correctly or the thread is not seated in the tension disk properly.

Install a brand new needle if you haven't already done so.

If it continues, this information about bird nesting could be helpful:

Sewing Machine Thread Bunching Up Here Why

Why Do Get Bunched Up Thread Under My Fabric

8 Tips to Fix Birdnesting in Embroidery

Why Is the Thread Getting Tangled Up Under My Material When Use My Sewing...

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Check your bobbin case if it looks like it has and feels like there are barbs on it they catch the thread time for a new bobbin case. I had mine less than 2 months and had to get one my machine sews and embroiders great now

it's possible that the motherboard that controls the embroidery
has a problem that needs servicing

Refer to your machine for cleaning the bobbin area.

You will need to clean this area often as lint and thread snips can build up can cause the bobbin feed to malfunction.

If this continues after you have cleaned the machine, the timing may need to be adjusted by a sewing machine tech.

I think you may have forgotten to put on the Q presser foot.

Try putting a new sewing machine needle in and make sure the eye of the needle is facing the right way. Needles look like they should go just anyway, but if they aren't in right, it could cause the problem you are having.

the needle thread tension is wrong
bunching up under the material indicates that it is too loose

You need to do a tension test
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(To do this test, adjust your tension setting to normal or medium or 5 or something in the middle. Raise the presser foot and pull the thread through the tension. It should pull easily!! Lower the presser foot and pull the thread. It should pull noticeably harder.)
If it doesn’t work this way then you probably have a piece of thread or lint stuck inside the tension discs. To remove it, turn the tension to 0 zero and raise the presser foot.Using a small screwdriver, open the space between the discs and spray with canned or compressed air. The stuff should come out. Do the tension test again to make sure you got everything and then try sewing again.
sewman7