I cannot see REQUIRED ITEMS. there is no change in the number of products. even though i created a boom
BOM is created once, to specify what you will make in future production runs.
Work Order specifies jobs to perform in a single production run, according to the specifications of the BOM.
Your error message is saying that your work order is not getting data correctly from the BOM.
Show images of you BOM and your Work Order and someone may help.