Unable to connect to world

I'm not able to connect to my friends world. Before the update I had no problem.

I'm using Win10, my friend is using xBox one... same version: v1.8.0

the only message I get is "Unable to connect to world"

 

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UPDATE

my sister logged in and tried to get into my friends world and it worked! After this I tried to and was finally able to get into my friends world on xBox. No idea what the problem was... I didn't changed anything.