Not Selected Checkbox

Hi,

I am new in wordpress and I use contact form 7 in my site. I have a checkbox which has only one option. everything works fine, but when I don’t select the checkbox in the form and submit the form , I can get all fields by email except checkbox’s value. So I’d like to receive a value like” Not Selected ” once people not check it.

Thanks for your help

https://www.ads-software.com/plugins/contact-form-7/