Thank you for reaching out to the community!
I am sorry to hear that the email addresses that you are trying to send to are bouncing. However, this is something that happens at the receiving end and will not be a reason that we would give a refund. I do want to help you understand bounces so that when this happens again, you are well informed.
Bounces are a signal that is sent back from the receiving mail server to tell the sender that the email could not be delivered. There are many reasons for bounces, although, they are all related to the recipient's mail server rejecting the message. Here is a helpful article that explains bounces in more detail.
I hope that this helps clear things up.
Please let us know if there is anything else we can do for you.