Thank you for letting us know about the trouble you are having with the coupon and the ability for those that purchase it to share it. We have tested it and it is working on the live version. If you were trying to test the feature from within the test/preview, then the share function cannot work. When did you notice the lack of ability to share? What were you doing exactly, was it is from within the preview?
To better assist you, please provide additional information as to what exactly you mean so we can help resolve this issue for you.