Core component of SQL Server for storing, processing, and securing data
This usually means one of these situations is happening:
- Wrong resource group
- Wrong subscription
- Database was restored/imported differently
- Portal cache/desync issue
- Typo/case mismatch in server or DB Name
The important clue is "You can connect successfully from SQL Server Management Studio".
That means:
- Logical SQL endpoint is reachable
- database with that name is responding via the SQL engine
- connectivity/authentication is working