Technical resignation accepted but lien not given

Dear Sir, I applied for technical resignation from a Central Govt. Organisation X from Group A post with a relieving date of 04.12.2015 to take up another appointment in Central Govt. Organisation Y (through UPSC IES exam) with a joining date of 21.12.2015.I informed the administration in written about my appearance in UPSC IES exam.My probation was also closed and i was posted in permanent capacity. I asked for lien and admin told me to apply sepratly for lien so on three days before my relieving date i requested to retain my lien but administrative officers were not able to decide the lien since my relieving was on 04.12.2015 so i applied for extension in relieving upto 11.12.2015 so that they can decide lien. But on 10.12.2015 i was told orally by administrative officers that we cannot give you lien and you will be relieved with your earlier date of 04.12.2015, so they issued a relieving letter dated 10.12.2015 with relieving date of 04.12.2015 and i had no option but to accept it...Now i have following queries 1.I want to know whether i can get lien or not if i request them again? also they treated me off duty from 05.12.2015 to 10.12.2015 though i was in office till 10.12.2015... 2. is it possible for administration to change the relieving date from 04.12.2015 to 11.12.2015 if i request them in written again so that i can get salary for those extra days also ? 3. can i go back again to my parent organisation from railways if they approve my lien? 4. what shall i do if they don't consider any of the above requests? Please reply sir.. Thanks