same Item on muliple lines on in Partlist then Quantity not updated Correctly

Hi Team,

When we created the work order that time both the line Quantity updated correctly. but After the partlist is attached, and then the work order quantity is changed (F4801.UORG), the part list not getting updated correctly. The below screen showing the correct value.

1. Work order Data- Total Order Quantity F4801.UORG= 2800

1. BOM Data

When we change the Order Quantity to 5600 then that highlighted item 1st line value remains same and remaining quantity allocated to 2nd line. but as per the BOM value,

1 st line should be updated as 1021.44 instead of 510.72

and 2nd line should be updated as 1613.36 instead of 2124.08