Convert warning message "Mandatory Condition xxx is missing" to error

Dear all,

I have maintained a pricing procedure where condition type PR00 is mandatory. When the user has not maintained a record in VK11, the system displays a warning message "Pricing Error:Mandatory Condition PR00 is missing", with a green flag. When the user tries to save the order, there is a pop-up whether you want to edit the incompletion log or save the order.

How can I change this warning to error? I want a red flag error message, and the user should not be able to save the order, if there is no price.

Thank you in advance.