I have tried seemingly all options to connect my old SBG10 to the Surfboard app. Previously only managed with PC login.

I keep getting error 0000-1900.

I've done a complete factory reset of the device (twice) and it did the usual firmware update on the device.

I tried setting up the device via the app, scanning the QR code to input the password. No success.

So I set it up manually on the PC and set the password to at least 8 digit, with caps, lowers, numbers, and symbols to meet the apps criteria.

Still no luck. 

I am certain I am selecting the right device (SBG10), I am certain I have selected the right option (device already set up), I am certain I've typed in the right log in password (probably 15 times at this point).

I've granted full permissions as the requests came in. The Android device is literally 5 feet from the router. And again I've done two factory resets on this router device.

The Android device the App is on is connected ONLY to this router (via the default network name and password, and then later to custom network names and password). Mobile data was turned off. No other WiFi connected.

What can be going on here?