Ionic App redirect to the external application

Here the my code redirects to the Viber application, it’s not working anyone can help me to solve this problem?

my code
let prefix = this.gApp.platformIs(‘ios’) ? ‘com.apple.social.’ : ‘’;

        this.socialSharing.shareVia(
          prefix +'viber://',
          this.property.heading,
          null,
          this.property.heading,
          this.property.link,
        )

I tried
prefix +‘viber://’,
prefix +‘viber’,
viber
as a app name.
but its not working in ios application.