If a customer initially used Paypal to pay for their order and contacts us to place additional item, you'll need to create a new transaction as we can't directly charge and re-run their payment using their Paypal account. To make a new transaction, you'll need to:
Go to Braintree.
Hit Create New transaction hyperlink.
Enter the customer's name or email address in the search field.
Click the Id hyperlink
Hit Clone
Enter the amount for the additional order
Click Create Transaction.
Copy the transaction details
Go to Big Commerce.
Search for the order number.
Go to View Notes and paste the transaction details.
Hit Save.
https://drive.google.com/file/d/1CczfV2hMWv9M7VQWmxL55lUgPJtSnhZ5/view?usp=sharing