Tag creates “invalid mailbox syntax” error

I have the following issue.
On a two page multiform, submitter’s email tag [your-email] is created on page 1.
On the second page in Mail==>Additional Headers this tag is used as “Reply-to: [first-name] <[your-email]>” and it throws an “Invalid mailbox syntax is used in the Reply-to field” error. In multiform environment this tag [your-email] is showing-up only on page 1 of multiform and not on page 2.
This issue is not present on 1 page form or any CF7 if multiform is not used.
Thanks in advance for your support.