A way to take away the bad; Knock slowly into the gap between the pillow and the neck with a screwdriver, or tap gently with something. The original one is also sticky. If it is loose, you can take it off.
Grind a new flat surface, put sandpaper in a flat place and polish the piano pillow horizontally. To what extent? Just grind it to the original height, or it can be as high as 1.23 mm, but it must not be lower, otherwise it will not work.
After polishing, smooth the neck groove, clean it up, glue it and begin to paste it. After pasting, make sure that both sides are just right, not more than one side and less than one side. The gap between the pillow and the neck should be tight. It's done. It's OK as soon as the hand is dry. Generally, it is relatively high. You can find a knife to dig a groove in the pillow, make a little noise, or even try it until you know you just don't play.
Hehe, let's briefly talk about the process, which requires a certain degree of hands-on ability. If the conditions are not satisfied, or uncertain, take it to the music shop for repair. With professional equipment, it can be repaired, which is estimated to be tens of yuan. Remember to contact me to help you if you repair it yourself!