I understand that you see an email account on your iPhone that you're unable to remove. I'm happy to provide some help with this.
Often times when an email account like this shows up that you're unable to remove, it is related to a profile. You can use the information provided here to check for profiles:
Use parental controls on your iPhone, iPad, and iPod touch - Apple SupportBusinesses and schools often use profiles, which can turn on Restrictions. To find out if your device has a profile, go to Settings > General > Profiles. Contact your administrator or the person who set up the profile for more information.
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