I have my world settings on multiplayer, but when I check while the world is loaded it is off and unchangeable, I'm not sure if the bug is something about the setting being disabled or not, but it seems to be preventing me and my friends join worlds even though I place the settings for multiplayer on.
I have tried the link but when I go to the tab to where I report my issue it says they do not offer support over mobile devices and ask for it to be done on the computer experiencing the issue but my issue is on my current device.
I have been having the same issue with Multiplayer on android with the Minecraft 1.15.0.53 beta version for the past 3 months.