Starting November 1, 2020, Sesame Street is no longer available to stream on the HBO app.
HBO Max has a collection of episodes across 50 seasons of Sesame Street, as well as Season 51 which begins on November 12, 2020. If your subscription provider supports HBO Max, you can sign in to HBO Max through your provider on any supported device for no extra cost.
To learn more, please see I have HBO (HBO GO). Do I get HBO Max?