GlobalComix is not tracking where I last left off in reading

When I first started reading, the site bookmarked wherever I left off last in a series completely fine, but for some reason since a few weeks ago when I came back it no longer does that so I've completely lost my progress in two of the series I was reading. I managed to find where I left off in one and put it as a bookmark on my browser for back up. Any idea if/when this issue could be fixed or how I could fix it myself?