EUFYCAM E and Huawei phone NOT COMPATIBLE?

Dear everyone,

I bought 2 Camera Eufycam E few days ago.
Installation on WIFI was fine! Then I went out and it was impossible to connect to both of the camera with my phone network. Even inside the house close to the homebase I don’t have access to the camera. I have a Huawei P20. My phone wife is Samsung Galaxy A5 and it works well (same phone network)! So I moved her sim card into my phone for checking…and it was not working !!! So the issue should come from the Huawei itself…
I also downloaded the app on an Iphone from a friend 30miles from my home and it works pretty good on the phone network.
Do you have any suggestions ?!
thank you
Regards
Charles (FRANCE)