LEE SHIN YE Hi there! Unfortunately, there's a small bug with one of the widgets on that page (the random selector). Our development team is currently working on a fix. It should allow you to gain progress again in a few days.
LEE SHIN YE Hi there! It might take a few days for the problem to be resolved. If this is the last activity you need in order to gain a certificate of completion, you can email us at firstname.lastname@example.org and we can assist you from there.