Can a seller invoice be cancelled & refunded?

[HDW77]

My landlord unintentionally sent me an invoice for rent and is now having fees taken out because they did it like a merchant. They didn’t understand it needed to be a “friends and family” request. I paid the invoice and now they would like to send the money back and redo the transaction as “friends and family.” Can this user cancel the invoice and refund me or do we have to wait 30 days? Should they not claim the money yet?

[kernowlass]

@HDW77 

If they issue you a refund then the fee that they were charged when you sent the funds will NOT be returned as part of any refund issued.