Dear [Author Name],
We're sorry this isn't more positive news.
A "no" can mean a lot of things: the number of submissions, taste, or even just timing. A secret of this business is that "no" often has more to do with the above than the inherent quality of a piece. If you have sent work to Joyland you're probably also a reader of our magazine. We thank you for that and respect the time and effort you put into your work and sending it to us.
We encourage you to keep writing, keep sending work out, and to never stop because of rejections.