How to make a question matrix mandatory in kobotoolbox

Please can someone help me by providing instructions on how to make a question matrix mandatory in kobotoolbox. I have built a form and although the question matrix is marked as mandotory during testing, the question can simply be skipped??

Welcome to the community, @ritta_gain! You could download your form as XLSForm and then add a required column to it (if it does not have one) and then make it mandatory as outlined here.