How do I fix uneven thread tension on my XH2149-001?

If loops appear on the surface of the fabric, the upper tension is too tight — reduce it by turning the upper tension control dial to a lower number. If loops appear on the back of the fabric, the upper tension is too loose — increase it by turning the dial to a higher number. Also check that both the bobbin and upper thread are correctly threaded, as incorrect threading is a common cause of tension problems.