Stuck on "Generating world" screen when creating Old type world

The old world cannot be generating world or building world. Loading becomes stopped when it enters the old world. This bug was already in the previous version 1.16.220.50 on the android platform, and the problem is:
1. when I used all the experiment / non exp and education / non edu. I couldn't enter the world / load the old world,
2. if i use external storage and non external / application, old world won't load either. So please fix this bug immediately, the Mojang team.
My operating system is Android 10 and my device model is Samsung SM-A107F.
That is all and thank you!