Error number -9

Currently there is no way to invite friends through iOS application of Minecraft.

and if you try to login to Xbox it will give you an (error code -9) which I have asked on the Minecraft discord, no one has a fix to my problem.

back to the inviting friends I play mainly on mobile and console (ps4)

and I can only invite on console (ps4) even when I am hosting from iOS (mobile) 

you can only host from console (ps4) and invite friends 

example playing on ps4 you can invite on mobile you can not invite unless you are all on the same internet or lan cable