I search and found this:
To remove the account on your iPhone, tap Settings > Passwords & Accounts. Tap the email account that you want to remove. Tap Delete Account
except that the Delete Account button is not there... what should I do?
iPhone 11 Pro Max, iOS 13
Do you have access for changes to accounts restricted via Screen Time?
Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support
Do you have access for changes to accounts restricted via Screen Time?
Use parental controls on your child's iPhone, iPad, and iPod touch - Apple Support
Removing email account from IOS13?
