"Invite friend" button missing/gone

I was trying to invite my friends to my singleplayer world since i cant make a realm. So i trying to invite my friends but the "Invite friend" button on pause gone/missing. And i asked my friend to check his Minecraft when im in my world. And then my friend said nothing shows.

Is this a bug and are this can fixed?

(Note: im using Indonesia language.)

Device: Advan E1C 3G