Stop sharing photos between devices

Both myself and my wife share apple ids and iCloud for the past year but it looks like since the update any new photo taken appears on the others camera roll it wasn’t doing that before the update my wife uses her camera a lot for work and it’s a pain all her photos appearing on my camera roll is there anything that needs switching off since the update I don’t want to mess about with creating new Id and iCloud for my wife and it’s only just started doing this so guess it’s something to with the update as we’ve been sharing both ids and iCloud for a year thank you in advance