I haven't seen it today, but it is something that appears to crop up from time to time in the Play store with purchased apps. If rebooting doesn't fix it try clearing the cache and data in the Play Store app, or re-install the Play Store app.
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality. Are you a developer? | Terms of Service