I have used a touch & sew for 40 years - my daily go to machine. Two things - Bobbin has 2 indents that must fit in bobbin case. Also do not over fill do not go past last white circle. Before you wind next bobbin make sure machine is oiled & cleaned. Mine does not like any lint thread etc in area. Use a pipe cleaner to get all lint out before winding. Also rethread. That is the simplist thing, it sounds to simple but often works. Good luck I love mine.