Mobile menu not working

Hi, I have searched the forums and cannot find a solution as to why the mobile menu is not showing at all. I have turned off performance enhancements and used the css below, bu tthe mobile menu is not working (also the video on the home page is not working.

Can you advise?

@media only screen and (max-width: 1024px) {
nav.main_menu {
display: block !important;
}
#avia-menu .menu-item {
display: none;
}
.av-burger-menu-main.menu-item-avia-special {
display: block;
}
}