[WP Smush Pro] WP Smush Pro Telling Me to Upgrade to Pro

I installed WP Smush Pro on this website, but when I try to configure it, the plugin is saying that some features are unavailable unless I upgrade to Pro. However, according to our WPMU DEV account, the site is already using the Pro version so I can't upgrade. I've even uninstalled the plugin, downloaded the ZIP and tried installing it that way, but it did not fix the problem. The site is also using Hummingbird Pro and Defender Pro, but neither of those seems to have a problem.