Exchange header data from sub-route is not available in the camel main-route

Question

This is my main-route,

.process(startOperation(DISTRIBUTION, GET_HOTEL_AGGREGATOR_RATES_API_MOM))
                .log("Calling CredentialRoute")
                .bean(AggrHelper.class, "getCredential")
                .log("Making parallel calls to vault")
                .multicast()
                .parallelProcessing()
                .to("direct:AgencyCredentialProcessing", direct:LocalCredentialProcessing")
                .end()
                 .bean(RatesPreProcessor.class, "preProcess")


        from("direct:AgencyCredentialProcessing").errorHandler(noErrorHandler())
                 -- setting value in exchange header, which came from main route
               .end();

• Now i'm setting a value in the exchange header on sub-route(direct:AgencyCredentialProcessing), is not available once the control goes back to main-route. What configuration changes i need to that exchange changes in sub-route scope should be visible on main-route also.

Thanks in Advance, Raghavan