Airtel Chennai — MNP - Airtel not releasing

Address:

Chennai, Tamil Nadu

Hi,
I am having 3 airtel mobile connection. Since, the network was very poor at both my office and home, I wanted to port my Airtel no. to VODOFONE. But airtel is giving foolish reasons that i have contract with airtel (ie. CUG.) Then I removed form CUG again submitted the MNP request. They have rejected my porting request again stating that have outstanding. which is nothing but current month amount which is only 22Rs., 10Rs, and 15Rs.
already Airtel has my advance amount and they can adjust from that.
If Airtel is not able to resolve the issue, why they are not