To rid of the unwanted pre-paid appointments/ credits on client records, you will want to do the following:
View this tutorial for more information on how canceling and refunding Pre-Paid appointments work.
If you cancel a prepaid appointment, the money is automatically converted to Store Credit to use at a later date. You can then subtract the store credit from the original client and add store credit to the actual recipient's record. You'd then book a new appointment for the recipient, and you can use the added store credit to cover the cost at checkout. The actual credit card charge will still be under the original client's record, but the store credit will take care of the new appointment.