Feel cheated after paying double for same month just because MTN changed billing cycle

So this month Past I were billed twice yet I was up to date with my account just because MTN changed their billing cycle. Now I've paid twice for a service of one month for which I didn't receive. Yes that's right paid now twice monthly fees for contract minutes but won't get it. This isn't fair and ****************. Are you going to do that in the future or are you in financial ruins that you need a quick buck out of your clients? I didn't ask for you to change the cycle and if I didn't pay twice I'd be in the arrears for your mess up and I feel cheated out of money and put me in financial strain for this month as I had to pay double contract fees on my 5 (five) contracts and received not extra airtime or data bundles. What are you going to do about it as I'm now seriously looking to move over to another Service provider.