Wifi password on iPad changed itself to an old password.

My iPad connects to my work Wi-Fi daily and has been connecting to the newest password without issue for a month. Tonight, when I tried to connect it said the password was incorrect and when I looked at it, it was the password from a year ago. The password has been updated at least 4 times since then. Not sure why it would revert to an old password by itself. I re-entered the password I’ve been using for the past month and it connected without issue.