Apps on home screen getting undownloaded

I have one app that i try to download and does not work and i actually noticed that one app (watchboard) was appearing with a grey icon with a grey grid and i also noticed that it was not opening when i tapped on the app that means it is unusable.

Apps are getting undownloaded on my home screen and when i try to download them again it comes up with this error that says "Not Enough Storage".