Creating a Recurly API Key:
Navigate to Integrations > API Credentials and select "Add Private API Key" from the top right corner:
Give the key a name, and let Recurly know that it's being used for the Upzelo connection. Then hit 'Save Changes'.
Once your key has been created, you'll need to click on the eye icon to reveal it and then copy and paste into Upzelo:
You may wish to provide a 'Read only' key when using Upzelo Analytics, and then upgrade your key (or provide a new key) with write access when trying or subscribing to 'Retention'.