We cannot give refunds ourselves, but you can ask Apple for a refund.
When you purchase an app from the App Store, only Apple has access to the purchase information that is associated with your Apple ID. To protect your privacy, that data is not shared with developers.
As a result, we cannot give refunds ourselves because we have no access to any of the data from your purchases. If you are not happy with Things, you need to approach Apple and ask for a refund. If a refund is given or not is a decision that is made solely on Apple’s part.
You can find Apple’s guidelines on refunds here.