You are wrong to say everyone was cancelled a week ago. Seems like its a rolling process as they transfer folks over. For example, my next monthly payment is due on 13 Feb and my WorldPay account still shows RangersTV subscription as being 'live'. I expect RangersTV to cancel it and transfer it before 13 Feb but will be keeping an eye on things.
Do you know if the payment was taken by the old provider WorldPay? If so, you can cancel direct with them (that's always been the easiest way in truth). You should have been emailed a login and password from WorldPay when you first started your subscription (you did keep it, didn't you?). Simply login to the site linked below, click on your agreement ID and on the next page click on Cancel. Job's a good 'un.
In the meantime you are 'stuck' with the Unlimited package you've paid for until this time next month - then do as you planned with the new subscription.
If the payment has been taken by the new provider I have no idea other than contacting support. From WorldPay I always got a monthly email saying they'd taken my subs. Dunno if you did/do. If you can access your WorldPay account the debit will show in there. For banking, my WorldPay debits showed as follows, no idea what shows for the new provider:
PURCHASE - DOMESTIC GLASGOW G51 WWW.RANGERSFC.CO.UK(TV