Custom mail-tag issue

Hi,
When I customize the form-tag (ex. from “tel-430” to “your-mail”) the mail arrive with empty field. Considering that I have changed the equivalent mail-tag.(I have read this article http://contactform7.com/text-fields/#email).

This issue happen with all single-line input that have the default “mail-tag” changed (default mail-tag: “tel-434”, “your-message”, “your-name”, “your-subject”, etc.).

Thanks

https://wordpress.org/plugins/contact-form-7/