Charge us for a service you know you delivered on!!!

After months on end of poor connectivity and Rain not wanting to take responsibility regarding their network (instead blaming it on a device), I asked them to cancel my contract. They wrote back on 19 May 2025 to say they will cancel my contract. This was their response: "As per our telephonic conversation, we will be processing the cancellation of your 4G rainOne subscription, and it will be effective on the last day of the month/end of your bill cycle." Today I discover that I have an outstanding amount, Rain claiming that I got charged for non-usage of their sim card since May 2025! I called in twice and was on hold for 10 minutes per attempt. On the second attempt someone did answer (not audible at all) and could not give me a reasonable reason for charging me for non-usage. I informed the lady that I will only pay what I owe them (the one month I did not pay) and not anything above that. She proceeded to let me know that I will deal with their debt collectors and ended the call in my ear! I repeat: I will only pay for the one month!