Webview not working on my appbuilder

Hello,
I convert my wix website on an app builder (Goodbarber if you know it).
The trouble is when I want to show a page of my website on it, I get a bad resize.


That isn’t in fullscreen.
I was calling the support and they told me responsive feature is not compatible actually on Wix.
But I think we can get a better view with line code no ?
Like iframe or another way ?
Because on my app builder I can write in html or put an plugin with files as we want


I need some help because I’m just waiting it to publish my app on Android and Apple

(the wix function “My Mobile app” isn’t possible, I tried it and their design is bad and their support is very poor, I waited 1 month without success to publish my app on iOs platform…)