i subscribed to apple music but i thought it was a free trial

I first opened apple music and I saw an ad about apple music and it said something about a 3 months free trial so I purchased it thinking I wasn't going to get charged but I got charged $9.99 so I didn't expect that so I want to know if there's a way I can refund that purchase. I already checked the "report a problem" page but that purchase doesn't appear. what can I do?