When trying to log into the Parent Portal or Parent App, you may still see that you can select your old school if your child has recently moved between schools.
You aren't able to remove accounts yourself.
I can see both the new school and old school
You will need to contact your old school and ask them to remove your email address from your old profile.
If you can only see the old school
Follow the instructions above.
You will also need to contact your new school and ask them to set up an account for you. Once they have done this and let you know, you'll be able to set your password and log in.