I cannot drop a database

Is like some snapshot is still opened but where look I for?

I am really stuck

use master;

DROP DATABASE sysutility_mdv

Cannot drop the database 'sysutility_mdv', because it does not exist or you do not have permission.

--ALTER DATABASE sysutility_mdv SET SINGLE_USER WITH ROLLBACK IMMEDIATE
use master;
aLTER DATABASE sysutility_mdv  SET RESTRICTED_USER wITH ROLLBACK IMMEDIATE;
DROP DATABASE sysutility_mdv

Msg 5011, Level 14, State 5, Line 27
User does not have permission to alter database 'sysutility_mdv', the database does not exist, or the database is not in a state that allows access checks.
Msg 5069, Level 16, State 1, Line 27
ALTER DATABASE statement failed.

alter database sysutility_mdv set offline;