Editing MAIL FROM Header

Hello,

I'm getting the following from my external mail server:

2024:02:22-19:28:14 wahine exim-out[** do-not-reply@fw-notify.net P=<> R=smarthost_route T=smarthost_smtp H=smtp.protonmail.ch  SMTP error from remote mail server after end of data: 550 5.7.1 Submission not allowed for messages in which header from does not match MAIL FROM

The manual indicates that the ADD HEADER function under SMTP --> ADVANCED will also edit one; however, it does not indicate the syntax required.  From the error message above, it's clearly not changing the MAIL FROM header per my wishes.

Here are the instructions from the manual:

The specific syntax to go in the rule creation dialog is not specified.
See what I have:


I must have the syntax wrong somehow, and I'm tired of guessing.
Could someone help me out?

Thanks,

Douglas Almquist

Seattle