If you went ahead and updated the WPO365 | LOGIN plugin to version 20.0 and you have a premium paid extension installed, then you suddenly may see a notice informing you that an Unknown error occurred whilst checking your license key for WPO365 | xxx. Please try again. This information, however, is a false-positive and results from a faulty interpretation of the license check response.
We have recognized this issue and immediately fixed this and urge you to update the WPO365 | LOGIN plugin to version 21.1. It may take, however, up to 12 hours before the error disappears. We are sorry for any inconvenience!