Unable to deploy to backendless viewer

Yes. I have changed my main page to HomePage, but I still see LandingPageMobile as the first page when I open Volpass from viewer. Also when I click on the button “Join For Free” on LandingPageMobile, I see an error as shown in the attachment.


The same works Ok when I use web browser. The code on “Join for Free” button is simple-- On Click Event → Go to Home page.