Cancellation taking forever

I cancelled my contract and requested that my nr be migrated to prepaid. The money I had to pay for the cancellation was paid and it reflected on my account the next day. Everyday im being told it takes 24 hours it should be done the next day. Today i phone again just to hear its still not cancelled and theres a 30 day notice period. For what if the amount to cancel it has been paid. Why is this taking so long. The service i have been getting is pathetic