You can undo or reverse a voided credit card payment using the "void reversal" tool found in the "find check and issue refund" page in Toast. You can only reverse voided payments that occurred in the last 30 days; payments that were voided over 30 days ago can not be reversed. The link below will show you how to access this tool and process a void reversal locally.
Credit Card Payment Void Reversal Guide
Toast issues the following statement after processing a void reversal:
"Void reversals provide you with the ability to re-charge a guest's card when a payment has been accidentally voided. This amount will be charged to the guest as a new transaction and should be deposited in your account within 5-7 business days. Please note that these charges are subject to a greater chance of chargebacks and disputes."