Thanks @kernowlass for your response but unfortunately there is no link to issue a refund in the https://www.paypal.com/activity/payment/[TRANSACTION_ID] page. Doing a Search of the word refund on this page returns 3 results and all of them in this help message: Refund Information - Please accept or refuse this payment. If you accept this payment now and need to refund it later, the Issue a Refund link will be available on the transaction details page for 180 days after the payment was originally sent.
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