Hi Mohith,
Usually receiver agreement not found issue will occur when there is some problem with either the configuration or the test data used.
--> Since you confirmed that configuration is in place. why don't you trigger the data from RWB --> Test message and see in runtime how the corresponding interfaces [Sender and receiver] and its namespaces are used to determine the receiver at runtime.
--> Did you add the receiver interface under the receiver business system / service? if not add it and test the configuration in ID.
--> Test the RFC destination "INTEGRATION_DIRECTORY_HMI" from SM59.
--> If none of the options are working i suggest you to restart the Java stack
Regards
Bhargava Krishna