Unrecognized charge on my debit card

I just got this IPad and looked at my purchase history and there is nothing on your records, but my debit card was charged 54.99. Now I also signed up for the music but it said I have 3months free and my card would not be charged. I haven’t given My information to anyone. This is my 2nd day on my iPad. On my debit card it says ITunes check card 54.99. Can some please explain this to me.