DS-156 question: have you been to US before - not getting checked

[srividya_sr]

I filled DS-156 online for my parents who are going to apply for visitor visa. They have been to the US once before. For question 29 - "Have you ever been in the US?" I checked "yes" when filling the application. But when it generated the pdf, the yes box is not checked - but the when? and how long? subquestions got filled with appropriate entries. Did anyone face a similar problem? What was your solution?
I emailed VFS but did not get a useful reply. Appreciate your reply. Thanks!

[Murali]

You can make that check manually on printed copy.

[paccha9999]

I had the same problem during my visa interview. I just checked it manually using a black pen.

[srividya_sr]

Thanks Murali and paccha9999 for your responses. I will ask my parents to do the same.