How does a client uncheck a response in the input table?

I have an input table structured for "past" and "present" health conditions. Sometimes a patient incorrectly checks the wrong box, but can't undo it. I checked and they are correct. I can't undo a checked box either. Is there a setting I am missing?

If you were referring to this page: 

That is because you used radio button fields, that is how radio buttons work. If you want your users to be able to check and uncheck you should set Input table to checkbox:

Hope it helps.

Let us know if you have any further questions.

Thank you!

Thank you! I had no clue!