Analytics for over past 6 months

I am trying to get my website analytics for upto 6 months or the past year. I read in another forum post to use the API and tried using the “/spectrum/analytics/events/summary” and “spectrum/analytics/events/bytime” endpoints but I get 1033 unauthorized error. Is this because I am on a free plan? How can I view my website analytics for the past 6 months or one year