Hi,
please open Scenarios -> Package Design and check if the parameter Authentication is explicitly set to "none".
If the parameter is empty B1i will fall back to basic authentication.
The incoming test message send by dotnet, should be visible in Monitoring -> Process Control: Scenario Processes- Inbound for debugging.
Please also check for namespaces and maintain them at the inbound definition of your scenario step in case they're sent by dornet.
Best regards
Bastian