API error

I keep getting an error and I’m not sure why. I checked that API is enabled, the calendar is public, the correct ID is being used. Not sure how to troubleshoot this one.

Error calling GET https://www.googleapis.com/calendar/v3/calendars/always-at-aum.com_0m79fkl2il3olm43ubomhfdlho%40group.calendar.google.com/events?singleEvents=true&maxResults=2500&timeZone=UTC&timeMin=2018-01-07T00%3A00%3A00%2B00%3A00&timeMax=2019-02-05T23%3A59%3A59%2B00%3A00&key=AIzaSyAvYQxHC2R8Aike_Vz0sos96VG43zsmE9g: (403) Access Not Configured. Calendar API has not been used in project 282321782969 before or it is disabled. Enable it by visiting https://console.developers.google.com/apis/api/calendar.googleapis.com/overview?project=282321782969 then retry. If you enabled this API recently, wait a few minutes for the action to propagate to our systems and retry.

Please ensure that both your Google Calendar ID and API Key are valid and that the Google Calendar you want to display is public.