How do I fix an incorrect Payment amount on an invoice in Apex?

How do I fix an incorrect Payment amount on an invoice in Apex?

In order to fix an incorrect Payment on an active invoice in Apex please follow the below steps:
1. Corrections
  1. In order to reverse a payment that was posted incorrectly, open the specific reservation and click on the "Invoice" tab. Note that Supervisor Authorisation is not required to perform this action.
  1. Next select the payment amount the line item will be highlighted in green. 
  1. Click on the "Correct" button and confirm the correction by selecting "Yes" on the confirmation window.
  1. The "Correction Reason" window will appear, please enter the reason for the correction and select "OK".
  1. The transaction will be corrected and greyed out on the invoice. The corrected amount will be removed and the total of the invoice will have changed.
Please note
  1. A payment can only be corrected on the date it is posted, should the error only be discovered the following day (after end of day) a reversal needs to take place. Please see below for reversal instructions.
2. Reversals
  1. Should night audit already have taken place a reversal needs to occur. Reversals differ according to the payment type used on the invoice. Please see the differences below.
       Cash Payments
  1. To reverse a Cash payment a "Paid Out" has to be charged on the invoice.  Click on the "Invoice" tab and select the "Charge" button, the Charge window will open.
  1. Select the currency and "Paid Out" on the charge code list. Type in the reference and the amount that needs to be reversed, then select the "Post" button.
  1. Should Supervisor Authorisation be required enter your details. 
  1. A confirmation window will appear next click "Yes" to continue.
  1. The "Paid out" will reflect as a charge and the original outstanding amount will display on the invoice. You can now continue to post the correct payment type and amount as normal.
OR
  1. Another option to reverse a Cash payment is to post a negative Cash payment on the invoice. This is a separate setting that needs to be activated, please navigate to Administration -> General Administration -> Systems Defaults and Policies.
  1. On the "System Settings" page ensure the setting "Allow Debit Cash and Cheque" is ticked and save the changes.
  1. Click on the "Invoice" tab and select the "Pay" button, the payment window will open.
  1. Select the currency and the payment type "Cash" from the list of payment options. 
  1. Type in the reference and the amount that needs to be reversed with a (-) minus in front of the amount, then select the "Post" button.
  1. Should Supervisor Authorisation be required enter your details. 
  1. A confirmation window will appear click "Yes" to continue.
  1. The "Cash" amount will reflect as a charge and the original outstanding amount will display on the invoice. You can now continue to post the correct payment type and amount as normal.

       Credit Card and EFT Payments
  1. To reverse a Credit Card payment a negative payment has to be posted on the invoice. Click on the "Invoice" tab and select the "Pay" button, the payment window will open.
  1. Select the currency and the payment type credit card (master, visa, american express or diners club) or EFT from the list. 
  1. Type in the reference and the amount that needs to be reversed with a (-) minus in front of the amount, then select the "Post" button.
  1. Should Supervisor Authorisation be required enter your details. 
  1. A confirmation window will appear next click "Yes" to continue.
  1. The Credit Card or EFT payment will reflect as a charge on the invoice and the original outstanding amount will display on the invoice, thus reversing the payment.  You can now continue to post the correct payment type and amount as normal.