There are two methods to Void a Transaction:

If the Invoice has not yet been Posted, you can click on the small "Trash Can" icon to the right of the payment amount.

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If the Invoice has been Posted, click the "Void" button in the Task Bar.
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CheckIn will ask for confirmation, and then contact Payment Logistics to process the request.
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You can confirm the status of the Transaction by clicking on the small "i" icon next to the payment amount.

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