Pay protection while joining CPSE(PSU) from central government

While working in CISF as SI/Exe. i have applied through proper channel for the post of Asstt.Mgr(security) in ITDC, a CPSE. All the necessary certificates were submitted by me at the time of interview. After my selection i have submitted my technical resignation to CISF on 30.06.10 & i have joined ITDC on 01.07.10. My last basic pay in CISF on 30.06.10 was Rs.17360 including the Grade Pay and my increment was due on 01.07.10 i.e the date on which i have joined ITDC. Cisf people informed me that i have submitted a technical resignation which is treated as merely change in service, so all my benefits of previous service will be in continuity including granting of increment. However, ITDC has fixed me in in the pay scale of [deleted](IDA) i.e the basic pay was fixed at Rs.16400 and they have also not granted me any increment due on 01.07.10. Further they have rejected my request for pay protection. Moreover, they have not responded to any of my applications i have sent them during the last five years of my service. Kindly help me out whether im eligible for pay protection and increment due.