REGEX Select From Where Word NOT Found Difficulty

I need a regex to match phishing email names, where a specific name or word is NOT found.

For example…

John Smith (notmyemail@sodifh.com)
John Smith (notmyemail@SODI.com)
John Smith (jsmit34@gmail.com)
John Smith (myRealEmail@mymail.com)

Where the bottom email is the only legit email, and needs to be ignored.

I have tried similar to:

^(J|j)ohn.(S|s)mith.*\@^((?i)\bmymail\.com\b)*$

But this fails to select the 3 bad emails.
Also tried similar to:

^(J|j)ohn.(S|s)mith.*@gmail\.com

but this method only removes the Gmail one.

How can I properly pattern match to remove all bad emails regardless of letter case, and to only allow one domain (in this case mymail.com) and no others?

>Solution :

You may use this regex with a negative look ahead condition

^[jJ]ohn.[sS]mith[^@]*@(?!mymail\.com).+

RegEx Demo

RegEx Details:

• ^: Start
• [jJ]ohn: Match John or john
• .: Match any character
• [sS]mith[: Match Smith or smith
• [^@]*: Match 0 or kore of any character except @
• @: Match a @
• (?!mymail\.com): Negative lookahead to fail the match if we have mymail.com is at next position
• .+: Match 1+ of any character