johnberry Glad we got it resolved, just posting this here for others' benefit.
You need to create an API key on the GivEnergy portal. This is so Wonder Watt can control your inverter.
You can do this by going to Account Settings, then select Manage Account Security (top right hand side)
and then select 'Manage API Tokens'.
You can create a new API token there.
The relevant API scopes/permissions for Giv that are required for WW to work can be found in this thread: https://community.wonderwatt.com/d/8-new-octopus-cosy-tariff/23
