What's the proper way of updating themes (e.g. Farms 133 Theme Pack)?

So I tried updating to the latest version of Farms 133 Theme Pack. What I would usually do when I update this theme pack is I would do it through the use of an ftp client and would just upload the themes directly to the theme's folder. When I tried checking the themes on my dashboard, it says that I still need to update the theme. The current version is and it's telling me to update to This is the second time it happened. The first one was resolved when I re-installed the WPMUDEV dashboard plugin and re-uploaded the theme pack again. I tried to mimick what I did before but to no avail, it still says I need to update.

Am I doing something wrong here? Advice anyone?