Hi all ! I hope, that you can help me with my inquiry. As ecommerce business owner, one of buyer bought item but unfortunately the item wasn't on the stock. Immediately I contacted him via email, that the item is not on stock with apologies with no answer from his side. After 24hrs I contacted them via sms but no answer. I am trying to reach him and ask for his bank details for refund but unsuccessfully. What can I do ? I am not pretty sure, if will be any penalty for my side. Thank you so much.