When I push the button to sew, I get a message stating that the safety has been acitivated. There is no thread tangled and the needle is not bent.

Take it for service. It's probably been knocked out of time.

If the safety has been activated, there is something wrong with the machine that could potentially be dangerous--to the machine or you. You should probably take it to a technician.

The noise is because the machine is trying to raise or lower a needle and can't move. Several things to check. Did the needle break and jam in the bottom thread? Is the needle bent or jam? Did the thread jam in the bobbin area? I had a 'knot' of thread build up on the bottom and it hooked itself into the metal clip on the bobbin so that the needle couldn't raise. If thread jams in the bottom carefully cut the threads until you can free the hoop and material. Then check to make sure all pieces of thread and fuzz has been removed in the bobbin case. If it happens again check to see if the bobbin case or the throat plate is scratched or bent. If you are stitching Free Standing Lace on this machine or a piece with over 20,000 stitches I recommend starting with a new full bobbin and a new needle. As you get toward the bottom of the bobbin, thread seems to have a high likelihood of tangling or looping.

The motor locked up because the thread is tangled. Remove the tangled thread before continuing the operation.Clean the bobbin case to remove the tangled thread. After cleaning the bobbin case, insert the bobbin case properly. If the needle is bent or broken, replace the needle.Then, thread the upper thread properly, and continue the operation.
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I would suggest rethreading the machine to make sure the thread is not caught somewhere, & even change the needle or check to make sure the needle is in correctly & pushed all the way up in the needle holder
& if that doens't help then take it back to the repair shop & tell them about the problem

have you tried a new needle?
the needle may be bent or damaged--try rolling the needle on a flat surface to see if it's bent or not
Or the needle could be in backwards
Correct needle insertion
Correct needle insertion is mandatory for proper use of sewing machine.
Raise the needle bar to the highest point, then loosen the clamp screw to remove the old needle, place the new needle in the clamp with the flat side to the back of the machine or if using a round needle--the groove in the needle should face away from the shaft.
Push the needle all the way up to the stop or as far as it will go, then tighten the needle clamp screw

2.upper tension may be to tight--try 3 to 5

3.thread may be hanging up in bobbin case--check area for loose threads or lint

4.also clean under the needle plate for lint & loose threads

check to see if the thread has come off the thread take up lever

check the needle first.Bent or spurred needles will result in this action.

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upper tension/threading wrong?