Screen time keeps turning off

Hello, hope someone can help. A few times already I’ve gone to check both my daughter's screen time to add or remove permission and it keeps saying the passcode/pin is incorrect. I keep changing it and I put it in a secure database for me to remember. I use a random pin generator so It won’t be something common for our household. But every time I go and retrieve it and enter it. It says it’s the wrong passcode.

My Apple ID and passcode all have been changed as well to see if they are changing it by logging into my account and no, they don’t. Just recently my youngest daughter came to ask me to please enter the code so she can edit her friends contact, and I got the message again saying my code is invalid. Is there a fix for this? Is there a way I can see how or when it’s being changed? This is bothersome as I don’t want to make my kids feel as if I don’t trust them.

Also, just to add. When I do change the password and make changes to one phone the other resets as well.