I paid now give me what I paid for

I fell in arears for a bit after paying my account I was told to wait until the amount reflected on their system before they would credit me for my minutes and data that I paid for. Only to call in about a week later and having an agent Rudley explain the minutes and data is expired it's not their fault but I paid for minutes and data I won't receive. Fast to charge you for a service they don't deliver and pocket the paid for benefits but not so fast to allocate ****** minutes and data