hello, trying to add an email account to the iphone, but it does not allow me to add it. It says account restriction. this phone is restricted from creating mail accounts?

hello, trying to add an email account to the iphone, but it does not allow me to add it. It says account restriction. this phone is restricted from creating mail accounts?

I follow the steps: Settings -> mail -> "cellular data is not highlighted" then I click on accounts and the same, nothing is lid up so I cannot click on anything ? Any idea?

Thank you