Following the app update to version 3.3.1, new iOS 14 widgets are now available. The old widgets no longer work for iOS 14 users and may have disappeared or turned into new widgets.
After restarting the smartphone, the old widgets are back but with a message to install the new ones.
We encourage users to install the new iOS 14 widgets specially optimized for their smartphone and with new features (new designs, ability to stack widgets, place them anywhere on the dashboard...).
See How do I add a new iOS widget?