I also cannot log into the stream on the content provider's site. I had no problem with authorizing here.
There was a brief issue impacting the Spectrum TV app last night / early this morning. The issue has been resolved, thanks for your patience.
Unfortunately, this stream is not available with your cable subscription.
It is but I have come to expect regularly broken things with Spectrum.
Spectrum is having trouble tonight. You are starting to see complaints on the forum and on their Twitter feed. Nothing to do but wait till they fix it. It is everybody not just you.