#include <MsgBoxConstants.au3> ; to declare the Constants of MsgBox
Local $sRegex = "(?m).*(?: DE: (.*))(?: ID: (.*)){0,1}(?: MOTIF: (.*))(?: REF: (.*)){0,1}"
Local $sString = "PRELEVEMENT EUROPEEN 2001427553 DE: MUTUELLE DE L'INDUSTRIE DU PETROLE ID: FR69MIP108863 MOTIF: Prelevement 42CXK 024 de MIP du 01/" & @CRLF & _
"VIR RECU 0485970259S DE: CPAM VAR MOTIF: 180930001235180930001235 REF: 18093000123"
Local $sSubst = "Tiers:\t$1 \rid:\t$2 \rmotif:\t$3\r\r"
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