How to clear or delete auto fill username in all build-in HTC app

[TiTaNSt33L]

Since I have login to Mail build-in for my HTC One app and it is work perfectly. But after I remove my account whenever I try to type my username or email with same letter it will come up auto fill drop down list. I have concern whether I login to my other friend phone too. How can I remove auto fill from dropdown list in all build-in app

I also try to go to menu language input personal dictionary but nothing there too.