3082136 - HTTP POST call fails with 403 error while accessing iflows protected by x-csrf-token

The HTTP POST call fails with 403 error while the iflow is configured to be protected by x-csrf-token.
From the message monitor, there is message failed with following error:
com.sap.it.rt.adapter.http.api.exception.HttpResponseException: An internal server error occured: HTTP operation failed invoking <https://***> with statusCode: 403.

• SAP Cloud Integration
• SAP Integration Suite

CPI, Cloud Platform Integration, HCI, HANA Cloud Integration, HTTP header, parameter, value, Allowed Header, expression, Runtime Configuration, iFlow, Integration Flow, request, response, SOAP, HTTP, adapter, sender, endpoint, endpoint URL, SAP Cloud Platform Integration, SAP Cloud Integration, 403, x-csrf-token. , KBA , LOD-HCI-PI-CON-HTP , HTTP Adapter , Problem