i am facing an error about whats app api in webview port

we make webview port application
in my website i use what’s App api to redirect whats app in website hederer and footer

here is url check please : https://superduperbazaar.com/

check send your list button it working normally

But if download app which is make in viewport and that i clicked send your list
it not work it showing error

error is: net::ERR_UNKNOWN_URL_SCHEME

here is error url below :

https://www.screencast.com/t/7viSBmnk3ZcJ

need help please ??