Cancellation and incorrect Billing

I am very dissappointed at the service i have recieved from Rain. I cancelled 2 sim cards via the bot and recieved a reference number ***4. This was in May. On 10 June 2025, I sent a follow up email to witch i didnt recieve a reponse. I was contacted by an agent where all of this was communicated and she let me know that the querie is being escalated under ref ***4, now i have a bill of R1935.00 which i am not liable for as i have not recieved an services from 1 June 2025. I am very frustrated as you cant call them directly because there is no number for the call centre. I really do not know what to do next, I am not liable for this amount and it has to withdrawn.