Two minis
You will need to contact support. Follow the support link at the top of the page then the submit a request link located at the top right of that page. I don’t know if they are able to refund your friend especially with out them knowing but they may be able to refund your gems from your purchase.
The Burninator
The CS Team won’t refund your friend, according to a Dev post from some time past. Especially, if you are contacting them about it.
As JT noted, you may be able to get a refund for yourself, though.
Good luck.