Hidden switch on the washing machine.

This hidden switch is located in the lower right or left corner of the washing machine, on the surface there is a small cover.

To pry open this lid, use a coin and you will see dirty water flowing out. Additionally, you should also clean the rectangular filter box on the inside of the washing drum. Because if you do not clean it regularly after a period of use, a lot of lint will stick here, making clothes easily dirty after washing. So, it is best to remove this filter box every week to clean it.