Firmware of your STB is outdated Please update it
There are few reasons for this to happen:
Your Provider is running very old version of the Portal. For example 4.8.xx. The app is tested and working with 4.9.x and 5.x versions up to latest version
Your Provier's Portal settings have changed due to Upgrade from their side.
Sometimes Providers need to adjust their updated Portal to allow non-MAG devices to use it.
Your TV's security settings is causing this (Samsung Tizen TV's only). Most likely Portal has introduced different protection due to upgrade. To get around it, make sure you have full and correct Portal URL.
Correct Portal URL are like
Wrong Portal URL looks like
that redirects to
Some redirects are not supported on Tizen TV's