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The invoice has to still be open.
The employee has to have permission to be able to void payments.
If a payment is tied to a gateway (external system like credit cards, Astro Loyalty, etc), then the void has to be approved by the external system.
If a credit card charge has already batched, it can not be voided.
Pin based debit payments tend to not be voidable.
Payments/rebates from Astro and similar external systems tend to not be voidable after a random period of time. This can sometimes be almost immediate, and at other times, can still be voidable days later.
Payments on Invoices that haven't been closed can in general be voided by the employee (see exception list above)
If the payment is on a sale that was put on hold, the void can only occur at the register that the payment was made at.
How to void a payment :
Sale is rung up and cashier clicks Pay.
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