I have a simple form being submitted into a third-party form/db location (Acoustic) and I’m trying to prevent the page from being redirected after submission.

    <form method="post" action="my-form-url-goes-in-here">
      // form labels and fields
    </form>
    <button type="submit" id="mybtn">Submit</button>

I’ve tried using preventDefault() and return false as options to override that behavior but for some reason they don’t work.

    document.querySelector("#mybtn").addEventListener("click", function () {
      document.querySelector("form").submit(function (e) {
        e.preventDefault();

        return false;
      });
    });

What are some options for achieving this behavior.