ActionNotSupported WebService JMETER

Hi there fellow devs,

I'm trying to contact a webservice via Jmeter (3.0), and I get the following error:

<s:Envelope xmlns:s="http://ift.tt/18hkEkn"><s:Body><s:Fault><s:Code><s:Value>s:Sender</s:Value><s:Subcode><s:Value xmlns:a="http://ift.tt/1afJxuo">a:ActionNotSupported</s:Value></s:Subcode></s:Code><s:Reason><s:Text xml:lang="es-AR">The message with Action '' cannot be processed at the receiver, due to a ContractFilter mismatch at the EndpointDispatcher. This may be because of either a contract mismatch (mismatched Actions between sender and receiver) or a binding/security mismatch between the sender and the receiver.  Check that sender and receiver have the same contract and the same binding (including security requirements, e.g. Message, Transport, None).</s:Text></s:Reason></s:Fault></s:Body></s:Envelope>

I haven't encountered any issues contacting the webservice from SoapUI, so I'm wondering what could cause this problem.

You can see the screenshots here:

The HTTP Request within the tree, first part of the HTTP Request data, the HTTP Header Manager settings: http://ift.tt/2fAqpEr

Here are the results on SoapUI (works just fine):

Results and log

Is it possible that the way that SoapUI sends the requests differs from the way Jmeter does and that's why it works?

Please help. Thanks!