Purchasing an item

I purchased (2) song's in October 2015 and it was billed to my account. It was paid for when I paid that months bill. However I notice this months bill shows I am being charged we do for it again. Who do I talk to, or how do I get this handled?

Please Help- 2- songs 2- charges x 2 Months back to back. When it should have been a one time charge.