Try deleting it this way.  Go to the K-1 interview section here

Federal

Wages and Income

Then scroll way down to Business Items

Schedules K-1, Q - Click the Start or Update button

If the first screen says "Do you want to review Schedule K-1?". You have to answer yes and then click Update by  the Schedule K-1 type (LLC, S corp, trust). The next screen is the Summary screen listing all of the K-1 entered for that type of entity.  You can review, edit or delete it there.

One user found he had to add a fake name first.....

I figured out that I had to actually start fixing this problem by entering a fake K-1 name to the TurboTax request and then going back to the "Update the Schedule K-1" and deleting the fake K-1 name.  

You should be able to simply delete the form from form view. I experienced the same situation. I had a blank K-1 also, but there were 2 forms related to K-1s that I had to delete before the final check would let me go on.

I switched to form view, found the files with K-1 in their names and deleted both.