Error message in CJ20N not converting to warning

Dear Peers,

While doing project definition, few errors are occuring viz. Message ID CO Message No. 344 (Item Category)/ Message ID CN Message No. 756(Purchase order already exist)/ Message ID CN Message No. 752 (Goods Receipt already exist)/ Message ID CN Message No. 707 (Purchase order already exist)

Right now these messages are coming as information, i want to convert these to error. I try to do by adding the message id in production > shop floor control > system modification--> attributes of system messages

But the things are not working even after defining in configuration

Pls suggest

Mayank