Define Tolerances Group for customer

Path :SPRO-Financial accounting-Account receivable and account payable-Business truncations-incoming payments-manual incoming payments-Define tolerances(Customers)

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Company code                                 : your company code

Tolerance group                               : Blank

Description                                        :Tolerance group for your company code (it text field)

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Tolerance group are acceptable, permissible variations, 

and authorization given to the user of the company code to post a document simply, To post open item client and vendor item and to permit money discount.

but if you maintain tolerance group code you have to assign with respective objective 
otherwise sap system don't allow to post any business transactions