Are you able to try this course in an incognito browser or different browser and see if the behavior persists? If it still persists, would you kindly record a HAR file and send it to me?
The next step is to collect a HAR file from you. A HAR file is essentially a recording of you doing the action that is resulting in an error so we can take a look at it more closely to figure out what's going on.
These steps are specific to Google Chrome, which is available for download here.
Open the Developer Tools from the menu (Menu > More Tools > Developer tools), or by pressing F12 (or Fn-F12) on your keyboard.
Click on the Network tab
Look for a round button at the top left of the Network tab. Make sure it's red. If it's grey, click it once to start recording.
Turn on "Preserve log".
You can use the clear button (a circle with a diagonal line through it) right before trying to reproduce the issue to remove unnecessary header information.
Reproduce the issue.
Save the capture by right-clicking on the grid and choosing "Save as HAR with Content".
Save the file to the desired location on your computer and then attach it to your Support ticket, or email it to me if the file is too large.
