Snap chat weird or am I being lied to ?

If someone gets a new phone and phone number but their snap chat account is connected to their old device that they no longer have access to , can’t remember the password to the email that is linked to that account in order to reset the password and link to their new phone, would they still recieve 2 text messages containing two password reset codes and then two texts on a different thread saying “ your Snapchat account password has been changed “ but they claim that they weren’t able to get in to change their password and they don’t know why it says that. Could it be the old owner of the phone number because a few days ago there was another text in another thread saying “Snapchat:YOUR FRIEND HAS ADDED TO THEIR STORY! “ . Is it possible to be the old owner of the number or is this person lying and was able to access their Snapchat ?