How to create display name

Hello

I have everything working in the user import tool other than the display name. This is the name that you see in AD when u list the users. It will create the name but its first inital, last name. I want it to display the users full name

Ex

It lists btest, but I want it to say Bob Test when listed in AD. What field am I missing, I have tried Common-Name, Display-printable name...

Thanks