Everytime i try to join my friend's wolrd or they try to join mine, it says "Unable to connect to world"

I've had this problem since april I think but I thought it was a temporary bug. Yesterday I tried to join my friend's world ( i play from my pc and they play from Xbox one) and it said "unable to connect to world" so they tried to join mine and it said the same thing. Today we tried again with another friend who plays from IOS, i couldn't join their world but they could play in each others world, so the problem is obviusly mine (my friends and I have the same minecraft version). I tried searching on Internet what i should to and i've tried everything but nothing worked. I've checked the NAT type ad it's open, i've checked the setting of my microsoft account and it's all how it should be, I've tried disconnecting and reconnecting my account from minecraft but nothing worked. I really don't know how to deal with this problem so i decided to ask for help because i really don't know what to do anymore. I hope everything i said is clear and that there are no mistakes (if so, sorry but english is not my first langueage). I really hope this bug gets fixed or at least if someone could tell me what to do please, i would really appreciate it. I'll put a screenshot of the screen it shows me when it says "unable to connect the world". I hope you could help me and i hope this helped someone too.