return of a postpaid sim card

I want to return TWO postpaid SIM cards (They are not activated and still inside the box) that come together with the Iphone I bought. On the retourenservice shows that I cant return, on the hotline I dont manage to get a feedback, on the site and at the store (yes, I also went there) says that I can only return the phone. To get worse, it was sent and charged TWO postpaid SIM cards and I already have one., I know I can return within 14 days but the days are passing and O2 does not give me any solution and answer after trying for two days. I hope to receive a feedback here.