I know this is a simple question. I have years and years of sewing experience, but this one has me stumped. I can’t figure out why my machine tunnels the fabric in zigzagging. If I zigzag for seam edges it almost looks like a rolled hem. I have tried widening and bring it in from the edge it still does. If I sew a zigzag right down the middle it will still pull the fabric so that it rolls into the zigzag. I’ve adjusted tention which didn’t work. I have tried using the overedge foot, which I thought would help…not. I have seen nice flat zig zags so I know it can be done. I haven’t figured it out. Any suggestions?