Start over. With the online version (which I personally do NOT recommend for a first time user or first time business owner), it's just to much jumping through hoops at this point, to try and correct stuff. Since business stuff is the absolute first thing you deal with after the Personal Info section, it takes less time and is less confusing to just start over.
With the return open so you can edit it, click MY ACCOUNT at the top right and select the clear and start over option. Do note that if you have already paid your TT fees or registered, then starting over is not an option. do NOT pay anything, or register anything until you are done with your tax return entirely, and are ready to file it.
