Navbar disappearing on IOS

I am developing a cordova app which works fine on Android. But I have a problem with the navbar in IOS.
My app starts with a login form if I login with the Navbar covered with the statusbar the Navbar does not get rendered in the upcoming pages. It appears again if I do an orientation change.

I have included
iosDynamicNavbar: false,

and added this to css

html, body {
width: 100vw;
height: 100vh;
But still no luck.
Any suggestions would be appreciated!
Included images showing the error.

I am using WKWebview