Thanks alot
I deleted the Service name and recreated it again. It works fine now.
I am getting another error now
I configured the MY INBOX with all the mendatory notes installed on both (Gateway and backend). When I click on the Applicaiton, it does not show me any data in my inbox .
The error log shows that the RFC Error: Interface /IWPGW/IF_TGW_SRV_CONSTANT changed at runtime error.