How do I get the zig zag to work? Only getting straight stitch.

Check that the stitch width is set to something higher than zero.

The needle bar is probably stuck so it will not swing from side to side. If yours is an older mechanical machine (pre-1990's), it most likely needs a good cleaning and oiling. Use good quality sewing machine oil compatible with your machine (NOT 3-in-1, WD-40, cooking oil, or the oil you found in your grandmother's sewing basket). Consult the oiling and cleaning instructions in your manual.

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