I am generating project name-wise engineers invoices. I hide the product name in the invoice lines and added my engineers name instead of the product name. when I change my project name, it changed engineers name but when I save it also stored previous project engineers information instead of replacing previous engineers, and when I want to add price, subtotal is calculated but the total is not calculated and when I save data all subtotal, total price is being set automatically set to 0, I want to save everything with calculation and want to replace fully with engineers name when I change the project name.
 
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