Following this method allowed the billing address form to be moved to the shipping address page of the checkout, but entry of a billing address is optional now.
What I mean is, if the Next button is pressed on the page without entering any billing address details, the browser would still proceed onto the next page.
If I click Update button inside the billing form while nothing is entered, messages in red color are shown under appropriate fields, but clicking the Next button bellow lets the browser to proceed onto the next page.
How do I make entry of the billing address on the page to be required ? I want, if the Next button is pressed without a billing address entered, messages in red color to appear under applicable fields, and the browser not to proceed onto the next page until the billing address is entered and Next is clicked again.
p.s. "My billing and shipping address are the same" is not ticked.
