This content you will see, if your tenant is on migration. In this time you see the button Delve on the main nav, but you don´t get access.
To get Delve in the nect 24h:
1. Main Settings : Frist Relase ON
2. wait max. 24h
3. you get Delve
Options:
- User settings for Delve ( On or Off for every User)
- Admin settings at SharePoint admin Center: (On or Off for the tenant)