Supposably, you was overlock. Served it to you so to speak faithfully pretty long, eg, several months or even years. But unexpectedly now - and it fails. How to Apply in such case? In general, about this you learn from current article.
So, if you still decided their hands repair, then in the first instance necessary learn how perform repair overlock. For this purpose one may use yandex, or study specialized forum or community.
Hope you do not vain spent time and this article least little could help you solve this question. In the next article I will write how fix stool or trailer.