Did you send it as a gift using iTunes?
You might be able to request a cancellation if you did, but otherwise probably not if you don't have the code. Otherwise you could try and use it yourself.
Contact Apple for support and service(Document Type: Document) Dec 6, 2017 Before you call, have your serial number ready. Or start your support request online and we'll connect you to an expert.Many phone numbers listed here only work when dialed from within their associated countries or regions. If your country or region is not listed, see your support options.https://support.apple.com/en-us/HT201232