I am guessing that I am not going to hear from you and my refund is not coming.
I would recommend that you should look after your customers better. I see that you currently have 16 1-star reviews and these are all from people who have purchased your product and it has not worked for them. If you just refunded these people they would not give you the 1-star review and you would have a better rating.
Also new customers would have the confidence in getting your plugin knowing that they were not taking a gamble on it. Currently they have to buy to see if it really works for them and if it doesn’t they have blown their money like I have.
I think that you are reducing your business success by not looking after people.