Transactions suspended pending cancellation

I sent notice of cancellation of my contract which is due to expire on 24-04-16 and got a call from the cancellations and was told cancellation will only be in April. I have been trying the whole day to buy data but I keep getting an error saying my tariff cannot be changed. I called the call centre and was told I cannot buy data because there is a pending cancellation. What ****ed up **** is that? Am I being punished now for cancelling my contract? Don't you maybe think I am cancelling because of bad network and service?