Rain Sim card

I recently got bad experience from rain, I took their Sim card in March and last month I cancelled the Sim card on my rain app last month and they still debited my account and told me that is the service fee, I haven't been using the Sim card for the past 2months and yet they debited even after I cancelled, all I want is my R250 back because I haven't been using the Sim for 2months.