Lack of 1099-B from a startup that shutdown. Declaring loss on return

I bought 10,000 shares of common stock from a startup where I worked until 2017. Last year, I got a letter saying that they were shutting down. I didn't get a 1099-B from them. 

I tried live online help, and I don't think the person could help me since they thought that 1099-B was necessary. I received none.

I did the following while entering my tax return. I followed this post:

• I chose "Long Term did not receive 1099-B form"
• Total Proceed - Enter $0
• Total Cost - Entered the actual cost of purchase

It still asks for 1099-B as shown in the snapshot below:

I am still being asked for a 1099-B. I didn't receive one. 

How do I declare this stock purchase as worthless?