How can I connect an On-prem Microsoft SQL DB with SAP CPI?

I have a local Microsoft SQLExpress DB instance. It is already connected with the SAP Cloud connector and mapped with an individual Virtual Host. Furthermore the needed JDBC Driver was added to the sap cpi. (JDBC Driver successfully started.)

The Configuration Parameters for the JDBC Data Source are following:

JDBC URL jdbc:sqlserver://sqlexpress:1433;databaseName=master

Cloud Connector true

The next step was to create an iflow, which can be accessed by postman and wiht an Request Reply and a jdbc connection it should be possible to get infos from the database.

But the iflow Artifact is since 2 hours just processing.

I dont know what is wrong. I assume that the connection is successful, otherwise there should be a connection error... shouldnt it?

Thousand thanks in advance