Error while creating OBC order V+D New Activation. Order is not created.

Error returned : 73 = failed to get serial number from arbor, error code : 0752

<soapenv:Envelope xmlns:soapenv="http://schemas.xmlsoap.org/soap/envelope/" xmlns:ser="http://server.api.nep.mobinets.com/">
<soapenv:Header/>
<soapenv:Body>
<ser:arborWOOBC_fCNAOBC>
<fAppType>I</fAppType>
<fOLT>AZA1</fOLT>
<fFDHMDU>OOOO</fFDHMDU>
<fOBCTag>40QFM1448709571//OTXX837401</fOBCTag>
<fSubno>44444069</fSubno>
<fWOID>4444400169</fWOID>
<fUsage_Type>BG</fUsage_Type>
<fOrder_Type>INST</fOrder_Type>
<fNoOfSTBs>0</fNoOfSTBs>
<fUserID></fUserID>
<arborOrderId>444440069</arborOrderId>
</ser:arborWOOBC_fCNAOBC>
</soapenv:Body>
</soapenv:Envelope>

<soap:Envelope xmlns:soap="http://schemas.xmlsoap.org/soap/envelope/">
<SOAP-ENV:Header xmlns:SOAP-ENV="http://schemas.xmlsoap.org/soap/envelope/">
<wsse:Security soap:mustUnderstand="1" xmlns:wsse="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-secext-1.0.xsd" xmlns:wsu="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-wssecurity-utility-1.0.xsd">
<wsse:UsernameToken wsu:Id="UsernameToken-40d2a842-0d43-40bb-9029-dd93ef032e04">
<wsse:Username>nep-api-key</wsse:Username>
<wsse:Password Type="http://docs.oasis-open.org/wss/2004/01/oasis-200401-wss-username-token-profile-1.0#PasswordText">mobinets@2017</wsse:Password>
</wsse:UsernameToken>
</wsse:Security>
</SOAP-ENV:Header>
<soap:Body>
<ns2:arborWOOBC_fCNAOBCResponse xmlns:ns2="http://server.api.nep.mobinets.com/">
<return>73</return>
</ns2:arborWOOBC_fCNAOBCResponse>
</soap:Body>
</soap:Envelope>