Thread bunching on bottom! Only doing it when sewing heavy nylon webbing. Doesn't matter the thread or bobbin or needle (already switched out). Sews fabric fine. Was working fine days ago on
Black/gray Reflective Webbing Tape Ribbon Sew on Reflective Stitching Nylon Webbing Dog Collar or Leash Purse Strap Webbing by the Yard - Etsy