Q: App Store Bill

Hello.

I purchased an app in the App Store last month for $9.99. My plan was just to try it out for a month and see how I would like it. I wasn't planning on continuing the app again the second month. It seems that I was charged again this month for it. Is there any way you can refund the charge and discontinue the app? I wasn't aware that the app charges would still continue even after the first month without my confirmation.

Thanks for your help.