Chunk loading while online sessions

So I was playing on severs and multiplayer. I noticed that Chunks load slow. It was not our internet speed though. The world that me and my brother made is really hard to load. So it takes about 12 minutes to load a chunk now. I noticed that even we made a new word, it will take about 4 minutes to load. This wasn't the phone however. Their phone is already Android 10 and used for gaming. Idk why the chunk takes so long to load