Hi @amy.rogers
At the risk of asking an obvious question, I notice that you are making the call on your sandbox url. When you check to see if the course is on the platform are you looking in prod or sandbox?
You could also try the following. Visit the platform and go to an existing course as an admin. The url in the browser bar will be something like this. https://entratasandbox.docebosaas.com/course/edit/229. Replace the course id, 229 in my example, with the number of the course you have created so, https://entratasandbox.docebosaas.com/course/edit/8154. Hit return and it should take you to the course you have created. This will at least confirm that it is accessible on the platform.
Thanks @pdevaney. Turns out it just took some time to be live in the system. I checked again a few hours later and the courses were there so it was successful! I just need to be more patient next time.