problem log out old account

good morning ,i have an old account on creative cloud but don't be able to eliminate this for access with another and new acconut.

the old mail is the account of ols school and the new in of my new school.

i've  disinstaled all creative cloun and re intalled but at the first access in automacally connect to the old accont.

please help me.

p.s. escuseme for my bad english