You can do this directly from your detailed transaction overview in just a couple easy steps.
Access transaction overview:
Click on your name in the top right and then select Billing:
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Next, click on the Wallet Transactions Button.
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Refund Transaction:
Now select the refund button next to the respective transaction that you would like to reimburse.
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Refund for the amount collected, which should automatically show. Not the full amount. Fees will be sent back with the refund.
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