On the Payment Details tab, you can provide information about documents associated with the bank payment, taxation details, and information on the exchange rates used for the document. 
The "Bank Payment (create)" form. The Payment Details tab
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In the Payment Amount field, specify the amount intended for specific document of the customer or related planning document.
The Planning Document field is available if the Use a payment calendar option is selected on the Administration > Settings > Cash Management form. The field is auto- populated in case the payment is based on a Money Transfer (Plan) or Money Payment (Plan) document.
If the Project Costing functionality is enabled in the application on the Administration > Settings > General Settings form, you can link a bank payment with a related project which you can select in the Project field (to find a project, start typing its name or code in the field).
In the VAT,% field (which is available for advance payments) _ you can view the VAT rate applicable to the document.
The VAT Amount field (which is available for advance payments) is populated with the VAT amount calculated in the currency of the bank account and in the national currency if they are different currencies.
Table mode
In Table mode, you can add documents to the list one by one, or you can add multiple documents at once by using the following buttons:
- Pick: To open the list of supplier documents and to manually select the unpaid documents from the list.
- Fill: To populate the list automatically with any of the supplier unpaid documents which amount will be equal to the payment amount.
The "Bank Payment (create)" form. The Payment Details tab in table mode
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In the Payment Amount column, specify how the payment amount is splitted split between documents.
Make sure that the sum in the Payment Amount column is equal to the amount in the Total field under the table.