DUO Authentication Proxy with Sonicwall NSA & Global VPN

I’ve setup the Proxy and the NSA according to the documentation. When I attempt to connect with GVC, I get a push notification to my phone through the DUO app. Once I accept, the GVC client seems to ‘reset’. The password I entered in GVC gets blanked out like it wants me to auth again. I never get connected.
Anyone seen this behavior?  It seems like I'm close but still missing some step.