Hello Bhargava Satish Kumar Vangapally& fellow readers,
This happens because, for the number range object SSCC-96 you have already created number ranges in the AII instance. So the AII system acts as a standalone system & the "Request Initial Range" button is hidden .
While for number range object GTIN, you have not created any number ranges in the AII instance yet.Hence it acts as a central number range administrative system & hence the "Request Initial Range" button is visible.
Refer the below links to solve the issue
http://scn.sap.com/thread/3357579
http://help.sap.com/saphelp_aii710/helpdata/en/45/f10e7561c706f9e10000000a155369/content.htm