@Players76: Are you able to recall exactly what the notification said, and any particular actions you were performing on the device at the time it appeared? Did you manually install the apps that have gone missing? It is possible that you have either restored a previous back up, which has removed any apps that have been installed since you last backed up, or the device has removed the apps due to a storage issue.
Have you tried swiping up from your Home screen, tapping on the Search field at the top of the Apps Drawer, and manually searching for the apps? If you open the Google Play Store and search for a relevant app, does it prompt you to install it or open it?
This is what i clicked onto.I transferred all my stuff on Saturday. When I go the apps they are still installed and says open but have gone off my screen pages
@Players76: If you manually search for the apps by following the steps in my previous reply, do they show up in the results? If so, press and hold on the app icon in the search results, then tap on 'Locate app' to take you to it's current location.
Go to One UI Home screen settings then check the apps aren't hidden. 
