The Multiplayer option is automatically disabled when I create a world and enter it, The Invite friends option is disabled and does not allow me to invite my friends, I can not enter the world of my friends

The Multiplayer option is automatically deactivated when I create a new world and enter it and I do not know why it happens since I have an advanced version of iOS, The option to invite my friends is deactivated and I do not know why that happens, It does not let me in to the worlds of my friends and I try to enter again and it appears to me "Could not connect to the world" The truth is not because since I use WiFi and it is very rare, I hope they solve it or send me a solution to apply it now that I can't play with them and it's very sad to play alone.

A hug and a greeting.