Impossible to cancel Hauwei Cloud Subscription.

A year ago, I switched from Hauwei to iPhone, Havent used a Hauwei in over a year, yet they still debit me R44.99 a month for Hauwei cloud storage. I tried to cancel the the subscription, but have realized they make it impossible. Chatted to the support tech guy on they Website chat box. They asked for all this infomaiton, even the serial number which I was able to give them, but they still wont cancel it. They want me to 'Send screenshot of carrier app", they want me to "Send phone bill for last three months", things that don't relate to someone who hasn't had the phone for over a year. I'm no longer in South Africa, so I cant even go into the bank to do a stop order. I'll probably have to resort to cancelling the card number. So disappointed.