CellC refuses to release cell number

I cancelled my top up contract with final date 4 February 2016. Cell C however expects me to pay a full months subscription for 4 days of access. I refused. On the 2 nd of February the sim was blocked. I phoned them on the 5th where I was told a hogwash story that I am in arrears by a month as pre-paid/ top up contracts are not paid a month in advance. I have had this contract for a few years now and has been a client for 10, and have paid for all pre-paid/ top-up accounts in advance Now they refuse to release MY cellphone number to allow me to port to VODACOM. The number is registered in my name and this is a violation of my property rights. If they have a problem with payment they can take me to court and we can solve it there. They have an account number that they can sue me for, why not release my cell number so that I can go to a network provider that wants customers. This number is used by my son, currently studying in Durban while we stay in Klerksdorp. He now have no contact with us. If this number is not released today I will take this further. I will not respond to phone calls or emails, I WANT MY NUMBER!!! Please respond on Hello Peter for all to see