Still paying for cancelled booster bundle

I've canceled a booster bundle on my contract months ago, which has been confirmed by MTN. But I've been paying for it ever since even though I do not receive it. The bill amount on the app also reflects the correct amount but the debit order amount still includes the bundle. I'm patiently awaiting my refund in my bank account for the last few months of the non existent bundle, since this is *****.