What should I do if the No.2 horn in Northeast China can't make sound?

Probably because the whistle didn't open.

You can put the whistle in your mouth and open it with saliva, or you can take a small amount of cold water and dip it in water repeatedly to open it.

The traditional suona tube has eight holes, which are pressed by the index finger, middle finger, ring finger and little finger of the right hand and the thumb, index finger, middle finger and ring finger of the left hand (left and right can be changed according to different users) to control the pitch.

The way of pronunciation is to put a reed flute (that is, reed) in your mouth and blow it hard to make it vibrate and sound. After being amplified by the vibration of wooden pipes and metal bowls, it becomes the sound of suona.