Hi friend,this is a video about how to adjust the tension of the thread, you can watch this tutorial to see if it can solve your problem. ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-fDwLHlTcXBw.htmlsi=RUO_d9Lo20IWochU If you have more questions, please contact our engineers and they will give you a detailed solution in time. Here is their contact information. Leo Wang WhatsApp:+86 18900636028 Email:service02@ebaima.com Facebook:facebook.com/profile.php?id=100087896671268 Luke Ren WhatsApp:+86 18961517173 Email:service03@ebaima.com Facebook:facebook.com/profile.php?id=100094317416802 Chirs Zhong WhatsApp:+86 18900631626 Email:service01@ebaima.com Facebook:facebook.com/profile.php?id=100073186299060