I have not been able to use the Spectrum app on our Roku Express and it was working. I unplugged the uninstalled the app, unplugged the Roku and waited a few minutes then reinstalled the Spectrum app with the same issue. I have also tried other things with no luck.
The Spectrum app does not ask for my username/password when I reinstall it. Is there a way I can force it to ask? Any other things I can also try?
I've seen the "Something went wrong" message before, but sometimes it's gone an hour later.. I'd try rebooting your cable modem and router, just to make sure it's nothing related to the app not talking to the Spectrum server correctly..