After you have disabled Stretch DB for all stretch tables in a database, you can disable it for the database. You can do this by selecting the database in SSMS and choosing the Task/Stretch/Disable option in the database context menu.

Alternatively, you can use Transact-SQL to achieve the same:

ALTER DATABASE Mila SET (REMOTE_DATA_ARCHIVE = OFF_WITHOUT_DATA_RECOVERY (MIGRATION_STATE = PAUSED));  

You can check if the action was successful by using this query:

SELECT * FROM sys.remote_data_archive_tables;  

You should get an empty set as the result of this query. As already mentioned for stretch tables, disabling Stretch DB does not drop a database remotely. You need to drop it by using the Azure management portal.