Hi Mark,
Kindly check your custom css code in the file: root/templates/ja_vitality/local/css/custom.css
.t4-megamenu .navbar-nav > li > a, .t4-megamenu .navbar-nav > li > .nav-link {
color: var(--mainnav-link-color);
font-size: 0.9375rem;
font-family: var(--heading-font-family);
font-weight: 500;
padding: 20px 40px;
transition: color 0.15s ease-in-out, background-color 0.15s ease-in-out, border-color 0.15s ease-in-out;
}
Try reducing the padding value so it can have enough space to show all menu item per line - along with the logo.