Old Emails on IPhone.

I have recently changed jobs and I always go to clean up all my data and login info when I do.  

in my outlook app on my iPhone, there is an option to add an office 365 account and my old work email address continues to pop up as an option to add.  I can’t figure out how to delete that old email or clear that info out of my phone or what app it is associated with. 

any help is appreciated.