If an admin user has indicated the booking payment method will be either cash, cheque or other, this payment can be edited. You won't be able to edit online payments.
To edit a booking payment, head to your booking module.
Use the filters to help locate the booking.
Click anywhere along the row of the booking you require to bring up its details.
You can edit the date paid, the method, the amount and whether the payment has been refunded or not.