Airtel
MNP not approved

I am using airtel number 9662060129. I have given MNP - Mobile Number Portability request on 15-Apr but till date the same is not approved.

While contacting to airtel, I received response that my number is under CUG and hence I can not port out.

I by my self choosen to go to CUG and now my self only choosen to go out from CUG and though why refusal?

Is this also described in MNP that CUG numbers can not be ported out untill not converted to indiviual account?

Please help me on subject matter.