Try to refresh if you have waited a minute or two already.
still it not working
please post a link to the course you are trying and I will try it too
Hi hope not to be so late. 
What worked for me was 1. Switch to white mode (I had dark mode activated), 2. I am using Firefox and to activate cookies I clicked on security shield then deactivated Enhanced Tracking Protection button, 3. I erase old stored CodeAlly cookies by pressing F12 >> Storage tab.