How to uncheck the Negotiated check box at Line level in BPA screen

Summary:

How to uncheck the Negotiated check box at Line level in BPA screen 

By default the Negotiated column is checked in BPA line

Request is to Uncheck the Negotiated check box by default when the page loads.

Note ; We tried the solution using Page composer - To uncheck the flag, but not able to save the user Input, each time the page loads it is getting reset to Uncheck.

Please provide the Pointers to achieve this.

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