Number of Review Words Differs from App to Website

Hi,

My Memrise app on my phone says I have 12 words to review for a course, while when I log into the website it has 57 for the same course?
Can anyone explain why this is? Does it have something to do with the course being downloaded or not?

I have just got this too… i have logged out and back in to no avail, I also had the course downloaded on my phone, up until now it worked well.

and a few minutes later its back to normal but now i should download the courses again.