You've built a form and you've had workers submit forms against it. If you want to edit the form, say remove a question you will find that question delete button is disabled. This is because you cannot delete form questions with results against it.
To remove form questions from a form, you will need to copy the form and archive the old one:
Go to Forms > Select Form and click Copy
In the copied form you can now delete the form question and add in a new one.
Tick the Publish box
Click Save and Close
Archive the old form
We suggest that you start to use version numbers to keep track of updated forms i.e.