OTA Distribution doesn't work anymore on IOS 13 ?

Hi everybody,

I want to distribute an ipa file by internal server using a html web interface and a link on a plist file .xml. This worked perfectly on IOS 12 and prevrious ! Now on IOS13 we get the error "App could not install. Try later". What's the new method to do a OTA Distribution under IOS13 and previous version of IOS ?

My plist file looks like:

and my html file looks like:

If anybody have an idea to how to resolve that it will be great ;-)
Thanks