Can't use Spotify App - invalidusername or password

I've already posted this on the forum, but have received no responses there.

What is the process for configuring the Spotify app credentials when one is
using Facebook for access?

I've tried everything I can think of including:
* Generating an app password in Facebook
* Using my spotify account credentials
* Using my facebook credentials
* Asking Spotify to generate a device key (leading to an Oh No, something
went wrong error from Spotify

None have worked. I have successfully installed and configured the spotify
protocol handler and logged in (or so the protocol handler says)

Any help would be much appreciated.

-steve