Possible Causes

Stuck balance wheel - Tires and wheels don't have precisely equal weight distribution. They'll be slightly heavier in some spots.

Machine runs noisily - It means that lint or oil are collected on the hook or needle bar. Moreover, a noisy machine could also be a sign of needle damage.

Machine keeps stitches - A dull, bent, or nicked needle can cause skipped stitches.

Puckered stitches - Tension pucker is caused while sewing with too much tension, thereby causing a stretch in the thread

Needle breaks easily - The needle could have been damaged or bent. The combination of needle size, thread size and fabric is incorrect.

Remedies

Stuck balance wheel - Adjust the Inner Knob of the Handwheel, Re-Thread the Sewing Machine, and remove the bobbin case.

Machine runs noisily - Simply clean the hook and feed dog as described in the instruction manual of your machine model. You can also oil the machine to make it operate smoothly.

Machine keeps stitches - Make sure that the thread is in the tension disk and the spool is placed correctly on the machine. Also, double-check to see if the bobbin is in the correct way and threaded tightly. Sometimes, a poorly wound bobbin is the culprit for skipped stitches. Good quality thread also plays a part in nice and even stitching.

Puckered stitches - Reduce the tension applied to the thread while it is being wound onto the lock stitch bobbin. Set the needle thread tension to be as light as possible while achieving a balanced stitch at the same time.

Needle breaks easily - Make sure the needle is correctly inserted with the flat side facing the back and pushed up into the machine as far as possible.

Hope it helps<33 (ps: pa-Brainliest para madaling makita ng iba)