Skipping stitches. you mentioned in your answer in Feb about retiming the machine. I have a

Question

you mentioned in your answer in Feb about retiming the machine. I have a Brother XL-3500 that decides to skip stitches or just not sew at all. I am very frustrated, as I use this machine for my business. I have tried everything I can think of. I have sewed for years, but never had this problem with any other mahcine. Bought this one about 15 months ago. I am in a remote area, can you give any pointers or suggestions on how to fix this?