Why can’t I see my Activities on Garmin Connect App

Do you see them in Garmin Connect Web? https://connect.garmin.com/modern/activities

No, I can’t see them there too. 
the activities are just visible at my Instinct watch. 

If you can't see any activities at all then you have logged in to the wrong account.

I can see mine but not in My Day or where I’d usually try to find…7d and 4w charts show blank but total distances shown…vivosport which i use to log sleep, also now not showing on my day… strange as all was okay up until a week or two ago…a bug?

If you can't see your new activities in Garmin Connect Web with the link I posted (https://connect.garmin.com/modern/activities) then there is a sync problem and that is why you don't see your data in My Day.

Try syncing with Garmin Express on a computer.

There is a recent bug not showing activities not having any name, on the MyDay screen. Access the activity through the News Feed, Calendar, or through Activities, and edit the name. Also change the setting for the default activity name to something else than "Untitled" - see the setting at https://connect.garmin.com/modern/settings 

Also check out the top, pinned thread in this subforum, for more details: Garmin Connect Mobile iOS - Mobile Apps & Web - Garmin Forums