Rajendra,
We are running version 2 of the HCM Fiori applications at our client, and in my IWFND/MAINT_SERVICE, the oData service version is still v1. The version of the oData service does not relate to the version of the app.
You have installed the correct software components(UIHR001 and GBX01HR), which give you access to version 2 of the Leave Req. application(SICF service - HCM_LRQ_CRE).
Can you provide the following?
1) In browser, hit F12 and navigate to "Console" - please provide a detailed screenshot
2) Screenshot from IWFND/ERROR_LOG
3) Verify if RFC system connection is maintained properly(correct client etc.)
4) Delete system aliases for the IWFND service HCM_LEAVE_REQ_CREATE_SRV and only assign 1 system alias(the correct backend system and client).
Post these results and I think SCN members will be able to help you out better.
Cheers,
Abhinav