Unable to connect to world on Minecraft PE v.1.16.200.53

My cousin and I have set up our Microsoft Xbox accounts and have been trying to connect to each other's Minecraft world for days now. We are not connected to the same local network, and we are not using an external server or a realm. We both are using Android
devices and are using Minecraft PE version 1.16.200.53. We are aware of the method that does not require connecting to the same network and are trying do that method. There have been instances when one of us could successfully join the other's world, but that
could be just luck, since we have never really narrowed down the conditions needed.

We have tried different methods such as (1) signing out of the Microsoft account then relogging, (2) exiting the Minecraft app before relogging, and (3) restarting our devices prior. We have also considered several factors. There are no issues with access
from the XBox privacy settings. Our internet connections are also not an issue. There was an instance when upon joining his world, I was prompted to download his used resource pact, and that one time allowed me to connect successfully. However, we still are
not certain if that's the cause. Overall, the goal is for him to be able to connect to my world instead of me connecting to him, but obviously there are problems with connecting to either of us. Is there a solve to this problem? This is very annoying, I hope
it get's fixed.

:)