I cant join my friends multipl game

I can't join my special friends' (BicoastalMean38) multipl game. If i try to join another friends' multipl game; i can join. I can join also mineville server easily. So i dont have any problem with my internet connection. I think this event is specific my friends(BicoastalMean38) game.I can join the same friends other worlds and he can mine but everybody (except me) can join my friends' world. I tried 3-4 days. I tried everything. I deleted the minecraft and set up again the problem is continue. I reseted my modem, i tried to connected vpn. The issue is continue. Please Help, Thank you...