data overage charges

I really need help with this. I religiously pay my monthly prepaid bill through auto pay. This month however my account states that my next bill isn't due until next month and the payment was successfully taken out of my bank account. I also received a text saying that my bill was successfully paid. However my data keeps turning off and saying that I've reached my limit and is now at 109% used and the date is still from my last months payment to today. I tried restarting my phone assuming it was a mistake but it's still not registering that my plan was paid for except on my account it's self. Am I going to get an overage fee? Because this is something that I might honestly leave the carrier for. I work over time to make sure my bills get paid and I can't afford any extra fees. Please help.