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1) Suppose that you have entered Invoice received for 4,000 AED for 2 items with different quantity and want to reduce the amount by 500 AED having total payable amount 3,500 AED (invoice received is not paid yet) :
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2) Create Debit Note using generate option, select Invoice correction Type:
3) In the Main Tab Enable Amount Only option, and make sure that Basis is filled with the correct invoice received and Transaction type is Invoice Correction:
4) In Inventory Tab you need to proportionally(!) allocate the amount that should be reduced from item cost:
5) In Settlements Tab press fill Fill by Balance button and make sure that Basis Invoice Received was picked to the list as the amount 500 AED will be reduced from payable balance of this picked Invoice Received:
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