Meghan and Harry had initially signed a production deal - thought to be in excess of US$100 million ($154m) - with Netflix in 2020 but are yet to produce any content for the streaming platform.
News of the series' cancellation comes just days after Netflix announced it had suffered a loss of 200,000 subscribers in a trading update released in mid-April and were looking at the idea of including adverts following the dip.
In a statement, Netflix boss William Ackman said: "While Netflix's business is fundamentally simple to understand, in light of recent events, we have lost confidence in our ability to predict the company's future prospects with a sufficient degree of certainty."