Does your prior attorney have a copy of the original stipulation? If so, he or she has to provide it to you. You can try filing the copy and explaining the circumstances to the Court but it is unlikely to be accepted.
Your second stip presumably settled your divorce therefore you must file that one or get your spouse to re - execute another.
The above is a general answer and is not considered legal advice. You should contact an attorney before proceeding to take any legal action, signing any papers or upon service of a summons.
The court will only accept an original stipulation in proper form meaning it is signed, dated and notarized. The other stipulation (2nd) one if it is missing these elements will not be accepted by the court.
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