Assassin's creed valhalla hiw to recover a save file

Hi all

Me and my boyfriend both been playing assassin's creed valhalla on my xbox account he had one save file and I had one. I've been playing on my save file and quickly had to do something so I've ask my boyfriend to save it for me but he accidentally save it over his save file, we tried to recover it from the autosave but all of his autosave have been deleted but I've still got my autosave from 4 mouths ago. Is there anyway we could recover the files back?

:)