"Unable to connect to world" each time I try to join friend

So I am having this problem where whenever I or my friend try to join each other's worlds in Minecraft Bedrock Edition, an error always pops up saying "Unable to connect to world" without any other context. I am playing on Windows 10 Edition and my friend is playing on Xbox One Bedrock Edition. We've tried multiple things to try to solve this such as changing the multiplayer settings, appearing online/changing online status, and restarting Minecraft. None of these things have been working and it's pretty annoying. I have not found any other solutions to this problem, and I'm not even sure if it's a bug, but I can't join my friend and my friend can't join me. We are both on the same bedrock versions, v1.12.0 and none of us have changed any network settings or NAT or any of that. There was one time where we were able to join each other, but even before that, the same error came up a couple of times. Now ever since that one day we were able to play with each other, crossplaying has not worked for either of us.