HTTP Status 503: Service Unavailalbe Error in SSRS

Hello -

We are using SSRS on SQL Server 2008 R2 we can access our reports via the Web Service URLhttps://tfs.rosetta.com:443/ReportServer

But cannot access the reports from the Reports Manager URL http://tfs.rosetta.com:80/Reports we get the HTTP status 503: Serive Unavailable. I attached a screenshot of the error.

I have read many post and have tried to disable IPv6, reset IIS and I'm at a lost of what could be causing this issue. Any help or insight would be greatly appreciated.

Regards,

David