Fidelity ADT Contract termination

After we review household finances we decided to terminated some of the contracts we have security system, bin cleaning etc. ADT was our service provider since 2013 August. Mid 2019 I contacted them to terminated their services they decrease the premium, in 2021 September 3 again I contacted them for same purpose they refused to do so, they request me to send email I have done that. After I send the email their response was that "the consultant will contact me" for what I don't know. December 15, 2021 debit order go off of which I did not authorised this debit order, today, 7 Jan 2022 I received statement of R602.90 of which I am not sure what they want.

I do not know why it is easy for ADT to sign up the client then it is very difficult when client terminate the contract, I feel ADT treat me unfairly. I don't think this is fair.