Querie on money demanded by National Security & Fire

I have been a client of Chubb now known as National Security & Fire since 2006 up until I cancelled my membership on the 9th May 2018. The cancellation was with immediate effect because I felt that Chubb has broken the contract and was taking a risk with my family and possessions. On the 9th May, my daughter was in the house when she had that people were breaking in at the garage. The alarm was off but she tried pressing the panic button several times without any response. Eventually she armed the alarm and allowed it to ring with the hope that Chubb will at least respond but nothing happen and the ******* escaped when the alarm was ringing. She ended up calling me at work which is further that Chubb offices. I arrived there and still there was no response from Chubb and even the response of the police happened before Chubb. I went to the Chubb offices only to find that they have moved, as a client I was not aware of this move and after finding out where they have moved I discovered the company has also changed the name to National Security & Fire, which was also new to me. I then told them I am terminating my services with immediate effect. I was told to write a letter of termination which I did. After 3 days the manager came to my house to plead that I change my mind but I refused. Now they are sending me invoices that I owe them for 3 months and also one for 2017. I was up to date with my payments with them. My name is Eunice Molokwe , Cell *** of Mafikeng. House no. 9 Geranium Drive, Mafikeng, 2745