Onboarding 1.0 Unsupported Media Type - using Postman

[Eugene_D_Fourie]

Good day Community

I am trying to push a new candidate into ONB 1.0 using POST: https://sales-onboarding2.sapsf.eu/ONBPREM/Services/HRDataServiceEx.asmx

The body of the request:

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:hrd="http://ATS.online-onboarding.com/Client/HRDataServiceEx">
 <soapenv:Header>
 <hrd:CorrelationHeader> 
 <hrd:CorrelationId>?</hrd:CorrelationId>
 <hrd:SourceEndpoint>?</hrd:SourceEndpoint>
 </hrd:CorrelationHeader>
 </soapenv:Header>
 <soapenv:Body>
 <hrd:BeginSession>
 <hrd:Name>SFPART058405_ws</hrd:Name>
 <hrd:Password>Welcome1@</hrd:Password>
 </hrd:BeginSession>
 </soapenv:Body>
</soapenv:Envelope>

I then get the response 415: The server cannot service the request because the media type is unsupported.

Am I missing a parameter in the URI or from the header?