@tutrix how do i fix this problem?

wait for Alvina's answer 😉 

i am only a hobby programmer 😀 , but i would open the wpforo > wpf-includes > class-template.php at line 1520

 function nav_menu(){
if ( has_nav_menu( 'wpforo-menu' ) ){
$defaults = array(
'theme_location' => 'wpforo-menu',
'menu' => '',
'container' => '',
'container_class' => '',
'container_id' => '',
'menu_class' => 'wpf-menu',
'menu_id' => 'wpf-menu',
'echo' => true,
'fallback_cb' => 'wp_page_menu',
'before' => '',
'after' => '',
'link_before' => '',
'link_after' => '',
'items_wrap' => '<ul id="%1$s" class="%2$s">%3$s</ul>',
'depth' => 0,
'walker' => ''
);
wp_nav_menu( $defaults );
}
}

and

<ul id = "% 1 $ s" class = "% 2 $ s">% 3 $ s </ul>

replase with

<ul id="%1$s" class="wpf-menu">%3$s</ul>

you can try it at your on risk

ok, now I see one menu item (Members)

and I see the problem, your Mega Menu override the css class from wpforo Menu

<ul id="wpf-menu" class="menu accesspress_mag_mega_menu">
<ul id="wpf-menu" class="wpf-menu">

We see the issue. We are going to check it. Please wait a bit, I'll update the topic asap.

yes you have an empty mobile menu, so there is nothing to click

I tested your website with several browsers, all have just an empty menu, only the search icon is visible

please make a screenshot from you full foro desktop menu

there is no menu on desktop or mobile

only the search icon is visible

<div id="wpforo-menu">
<div class="wpf-left" style="display:table-cell">
<span class="wpf-res-menu"><i class="fas fa-bars"></i></span>
</div>
<div class="wpf-bar-right wpf-search">