SOAP Adapter Error in PI7.3

Hi Experts

We are on a project to upgrade PI7.0 to PI7.3. Currently we are facing an issue in SOAP adapter in PI7.3 where all interfaces are failing due to error -

Error in Plain Http Adapter Processing

The detailed error log is as follows -

<SAP:Error SOAP:mustUnderstand="1" xmlns:SAP="http://sap.com/xi/XI/Message/30" xmlns:SOAP="http://schemas.xmlsoap.org/soap/envelope/">

<SAP:Category>XIAdapter</SAP:Category>

<SAP:Code area="PLAINHTTP_ADAPTER">ATTRIBUTE_SERVER</SAP:Code>

<SAP:P1>500</SAP:P1>

<SAP:P2>Error during parsing of SOAP header</SAP:P2>

<SAP:P3><SOAP:Envelope xmlns:SOAP="http://schemas.xmlsoap.org/soap/envelope/"> <SOAP:Header> </SOAP:Header> <SOAP:Body> <SOAP:Fault xmlns:SOAP="SOAP:ClientError" _mce_href="http://schemas.xmlsoap.org/soap/envelope/"><faultcode>SOAP:Client</faultcode><faultstring>Error">http://schemas.xmlsoap.org/soap/envelope/"><faultcode>SOAP:Client</faultcode><faultstring>Error during parsing of SOAP header</faultstring><faultactor>http://sap.com/xi/XI/Message/30</faultactor><detail><SAP:Error SOAP:mustUnderstand="1" xmlns:SAP="XIProtocolhttp://sap.com/xi/XI/Message/30"><SAP:Category>XIProtocol</SAP:Category><SAP:Code area="PARSER">ITEM_MISSING</SAP:Code><SAP:P1>{http://schemas.xmlsoap.org/soap/envelope/}Envelope</SAP:P1><SAP:P2/><SAP:P3/><SAP:P4/><SAP:AdditionalText/><SAP:ApplicationFaultMessage namespace=""/><SAP:Stack>XML element {http://schemas.xmlsoap.org/soap/envelope/}Envelope missing in SOAP message header (SAP XI Extension) </SAP:Stack></SAP:Error></detail></SOAP:Fault> </SOAP:Body> </SOAP:Envelope></SAP:P3>

<SAP:P4 />
<SAP:AdditionalText />
<SAP:Stack>HTTP server code 500 reason Error during parsing of SOAP header explanation <SOAP:Envelope xmlns:SOAP="http://schemas.xmlsoap.org/soap/envelope/"> <SOAP:Header> </SOAP:Header> <SOAP:Body> <SOAP:Fault xmlns:SOAP="SOAP:ClientError" _mce_href="http://schemas.xmlsoap.org/soap/envelope/"><faultcode>SOAP:Client</faultcode><faultstring>Error">http://schemas.xmlsoap.org/soap/envelope/"><faultcode>SOAP:Client</faultcode><faultstring>Error during parsing of SOAP header</faultstring><faultactor>http://sap.com/xi/XI/Message/30</faultactor><detail><SAP:Error SOAP:mustUnderstand="1" xmlns:SAP="XIProtocolhttp://sap.com/xi/XI/Message/30"><SAP:Category>XIProtocol</SAP:Category><SAP:Code area="PARSER">ITEM_MISSING</SAP:Code><SAP:P1>{http://schemas.xmlsoap.org/soap/envelope/}Envelope</SAP:P1><SAP:P2/><SAP:P3/><SAP:P4/><SAP:AdditionalText/><SAP:ApplicationFaultMessage namespace=""/><SAP:Stack>XML element {http://schemas.xmlsoap.org/soap/envelope/}Envelope missing in SOAP message header (SAP XI Extension) </SAP:Stack></SAP:Error></detail></SOAP:Fault> </SOAP:Body> </SOAP:Envelope></SAP:Stack>
<SAP:Retry>M</SAP:Retry>
</SAP:Error>

Have you come across this error in any scenarios? if yes, please help me with the solution.

Regards

Vikas