Hi there!

Thanks for reaching out to us.

Please use the following code in your custom CSS:

.offcanvas-menu .offcanvas-inner ul.menu>li.menu-parent li.menu-parent .menu-toggler {
    top: auto;
    transform: translateY(-100%);
    -webkit-transform: translateY(-100%);
}

It should help:)

Here is all about custom code placement in Helix Ultimate: https://www.joomshaper.com/documentation/helix-framework/custom-code-css-js-meta

Best Regards