How To Void Posted Receipt
A. Receipt Was Done Within Sales Invoice
If the payment was created within the Invoice (Sales Invoice > Enter Payment Button), the only way that you can void the payment is by voiding the Sales Invoice.
Void the Invoice first and then, void the receipt.
Note: When the Invoice is voided it will reopen the sales order associated with it.
And you should be able to VOID the receipt now
B. Receipt Was Created Separate from the Sales Invoice
If the payment was created separately from the Sales Invoice (Customer > New Receipt)
Deallocate Payment from the Invoice first. (it only applies if the receipt was allocated, you can void directly the receipt if not allocated)
Then, void the Receipt.
Voiding the receipt will create a void transaction receipt and will cancel the amount in the receipt on the Bank as well as in the Account Codes. When Invoice was from a Sales Order, it will open the Sales Order after voiding the Invoice
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