Hi, have you ticked the checklists end of lesson and if so you may like empty cache refresh and try again. Try URL in a different browser or a mobile device.

Kindly let us know how you get on.

Make sure everything is checked off so you can advance just like in previous lessons, and if all else fails, try a simple restart of your machine. :) Let me know if you need any more help.

Have you ticked everything as completed at the end of lesson 4, not that that should stop you. Try logging out and back in again.