Refund Request: Subscriptions

I purchased a trial for an app that said the trial was for 7 days, but I was instead debited today, a day earlier from when my trial period is supposed to end and when I contacted the apps support team I got a mail back saying my subscriptions are manged by apple and I have to raise a request with Apple. When I do try to raise a refund request, I am unable to view nor select the subscription under the drop-down list of options.