Invoice States
There are 3 states for an invoice:
Awaiting Payment- This is the default state when an invoice is created. It means that the invoice has been created but the customer has not yet paid.Under Review- This occurs when a proof of payment is uploaded. It means that the proof of payment has been uploaded but the proof of payment has not yet reviewed yet.Fully Paid- This is when you marked the invoice as fully paid.Partially Paid- This is when you marked the invoice as partially paid.Paid in Cash- This is when you marked the invoice as paid in cash. You can mark the invoice as paid in cash if the customer paid in cash and you have no proof of payment.Cancelled- This is when you marked the invoice as cancelled.
The flow of the states are as follows:

Note that you can't go back from one state to another. For example, you can't go from
Fully PaidtoAwaiting Payment.