#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m)(.*)(@\s?)(.*[^(\s\(\d+\))])(\s\(\d+\))?"
Local $sString = "Title@ First Name Last Name (12)" & @CRLF & _
"Second Title@ First Name Last Name"
Local $sSubst = "$3"
Local $sResult = StringRegExpReplace($sString, $sRegex, $sSubst)
MsgBox($MB_SYSTEMMODAL, "Result", $sResult)
Please keep in mind that these code samples are automatically generated and are not guaranteed to work. If you find any syntax errors, feel free to submit a bug report. For a full regex reference for AutoIt, please visit: https://www.autoitscript.com/autoit3/docs/functions/StringRegExp.htm