This iPhone is restricted from creating email accounts?

My phone is off the charts bonkers! I have a 6S that I always have memory issues with and now battery issues. However, recently I had to delete the email tab on my phone so make more room for something I needed urgently on my phone. When I reinstalled email app it says “ account restriction” this phone is restricted from making new email accounts. Ok?? Why?!??

i have gone into settings then general and I don’t have a restriction option on my list of options anywhere. Why?

i truly feel like my phone has been taken over by a virus or something. There is a ton weird with it lately but I don’t want to get on other subjects. Just need my email up and running again. Help!? Please......