Where should I oil my unidentified sewing machine?

Depends on your machine. The owner's manual is the best source for care of your machine.

If it is a mechanical machine (not computerized), even though the owner's manual does not specify thorough oiling, when they are vintage machines, they will need some oiling. As machines and the oil get older, the oil begins to dry and sticky. Frequently, this will cause the machine's moving parts to seize. Here are some suggestions if you are interested.

It was working now it seems to be frozen the needle part wont move

Sharon, some machines don't require oiling.
You should read the machine's manual to double check.
Or you could check the machine's manufacture on-line.
Oiling a non-oiled machine can cause all kinds of problems.
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