Progress not sync'ed btwn iPad & Macbook Air

I am working through the Javascript course, I use both my Macbook Air & also my iPad to work through the steps. I notice they are never synched at the same lesson, the most recent lesson that I finished? I noticed today, both devices seemed to have jumped back 4 or 5 lessons too.

I am using the same login, (my google login) on both machines, so how can I keep my learning progress in synch & at the same lesson across the Macbook & iPad please?

the button to bring to last lesson I think is relying on local storage, but you can always go to the challenge to do from the list of challenges