How to repair the needle of my sewing machine?

Mine has a tightening screw. I'd call or take it to a sewing center that works on machines.

Should have a screw that holds needle in needs tightened and there is usually a flat side to needle so the needle should only go in one way.If screw is missing you'll need replacement get one from singer or maybe any fabric store might need to order one from singer

If you don't have hand strength like me, you might need to tighten with a pair of pliers or find someone strong enough to tighten it sufficiently.

Hi Jude,

I had to tighten mine with a screwdriver the other day.

It’s happened to me too. As mentioned above made sure the needle is positioned correctly as far as th flat side and tighten the screw well.

the casing on my sewing machine, the part that holds the needle in, I tried screwing the screw it in tighter and I notice it was cracked, so still haven't taken it to get fixed, using my grandmothers old treadle Singer sewing machine, it works great, its over 100 year old.

If the needle is put in incorrectly, it will not hold. Make sure you have the correct needle for your machine, and make sure to place it in facing the correct way. Mine will not stay put if placed in backwards. Hope you figure it out.