Sound core liberty 2 pro connection unstable issue


I have been using my earpieces for one and a half months. However, I face a connection stability issue recently (Started last 10 days ago). Like when I get into a mall with quite a amount of people, the music play started to be unstable. The music will on and off and hizzing sound. Back to one month ago, there would be this kind of issue. Does anyone know what causes this to happen? I am currently using Huawei P20 pro and play my music with Spotify.