App Store and Play Store refunds are reviewed and approved by Apple and Google, not by Bend, so they have the final say. If your request was denied, here are your options.
On iPhone
Apple handles all App Store refunds. You can submit another request or appeal the decision through Apple's refund page, adding any detail that supports your case.
On Android
Google handles all Play Store refunds. You can submit another request or contact Google using Google's instructions.