Hello, I would like to know why my UMAP visualization results are so strange, can you give me some advice? Thanks! <img width="1158" alt="1d1d186d2859742e0794475acbc53b4" src="https://user-images.githubusercontent.com/128218544/226096498-5aaeebd6-e554-4074-b538-5d2a12fb04e4.png">