It could be possible there is thread, lint, other debris that has become wound into the machine's inner workings. Opening the machine and looking for things that don't belong and then carefully removing them may solve the problem. Also recommend refraining from running the machine's motor while the machine is locked to prevent damaging the motor. A better suggestion is taking your machine for service. It could very well benefit from a general overall checkup, cleaning, oiling, and adjustment.
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It could be possible there is thread, lint, other debris that has become wound into the machine's inner workings. Opening the machine and looking for things that don't belong and then carefully removing them may solve the problem. Also recommend refraining from running the machine's motor while the machine is locked to prevent damaging the motor. A better suggestion is taking your machine for service. It could very well benefit from a general overall checkup, cleaning, oiling, and adjustment.