Minecraft doesn't work for me?

I wanted to play with my girlfriend today and I downloaded Minecraft to my mobile phone, but whenever I want to join her or she comes to me (I made everything like in tt videos and the same internet doesn't work because we live very far away ):

Do you use realms or servers

Server

But your girlfriend is coming up? And is it a public server or did you suspend it?

Created by us, we also tried liveboarding but it didn't work for me

Hmm really hard to say. Can be many things

Oh.

Try to connect to a public server to see if it is up to your device

It does not work