instance_not_ready

When it happens

The instance cannot do this yet:

• it has no active signing key yet (right after it was created), so it cannot issue tokens;
• a production instance whose domain is not live has no sign-in pages yet, so the Backend API cannot create organization invitations or actor tokens, whose links point there.

What to do

Retry shortly. For a new production instance, finish the domain setup in the dashboard first (Domains).