How can I trigger the Google sign in flow when Google account is not set in the OS?

I’ve just got this from our testers:

“The user should be prompted with the Google Sign in flow if no account is set in the OS settings. This is a Google First Party Requirement”

If I remember correctly it worked automaticly when I used other iap plugins when I called the purchase method.
With UnityIAP I can’t call the purchase method because the initialization will fail and the controller object - which has the purchase method - is null.

Any idea?

Can you provide the documentation that the user is referring to? We do not handle authentication, we are pass through service for the Google store. Also, not sure what you mean “no account is set”. By definition, you need to be signed into an Android device with a valid account to use the device.