URGENT REQUEST FOR REFUND

I called rain mid-August to cancel my wifi connection on the first of September, they guided me on how to cancel the services and received an email confirming my cancelled subscription. on the 25th a debt order came through for September connection. I called them and also communicated via WhatsApp and requested a refund because I cancelled the services. they promised to call me and haven't received any calls. today they send a request to collect the router but nothing about my refund. I need my refund ASAP. you have no right to debit me after cancellation.