Whisperfish - The unofficial SailfishOS Signal client

I installed harbour-whisperfish-0.6.0-0.alpha_.6.armv7hl.rpm on my XA2 from openrepos.net.
When I opened the app, this appeared: “Enter your password”
I put in my regular phone password. I then tapped: “Accept”
This is what appeared next: “ERROR - Failed to setup Signal Client”

What should I do to correct this?