I’m afraid I’m not in a position to disable and one-by-one re-enable each plugin to find the one causing the conflict: it might not even be one running on the page; or it could be a theme (OceanWP) conflict.
However, the forms display correctly if I use their shortcode instead of inserting the form directly, a simple solution (I use Elementor). They are wonderful, I’m very grateful for them, and am happy this solution solved the problem! You can see one here if you wish. https://www.dappledlights.com/portrait-prices/