Contact Form 7

I’m using the Kordex theme and it apparently wants to only use an email address that matches the domain name for the response field. I would rather use my long-used email address, rather than set up a domain email address with a forwarder. HOW do I fix this? I keep getting syntax errors when I try to force my email address on the response field and the form will not work.

HOW do I get around this?