Open another app with intent url on Android

Hi I have a unity app which needs to get some data from an Android app on the same device,

The dev of the android app said I need to call this url which should open the app up get the data and then return to my app.

intent://#Intent;scheme=indiewallet;package={THE-ANDROID-APP};S.source=getaddress?success={MY-APP_URL_SCHEME};end

If this link is opened from the android web browser it does open up the app, however when I open this url from my unity app using Application.OpenUR, nothing happens.

Am I doing something wrong?

Thanks