I refunded this guest/renter, and now a chargeback occurred. You have debited me twice (once for the refund, and again for the chargeback). Why?

This usually occurs because the card issuer is not aware that a refund has been issued because it has not yet posted to your guest’s/renter’s card yet.  When the chargeback is received from the card issuer, the funds are automatically recaptured from your bank account. 

However, we will dispute the transaction with the card issuer showing proof that the refund has occurred and recover the duplicated credit from your guest/renter right away.  It is important to issue refunds in a timely manner and set clear expectations with your guest/renter about when the credit will be completed to prevent these occurrences.