To fix this problem:
Add in Custom JS:
<script type="text/javascript">jQuery('.navbar-nav').on('click', '.menu-item-language-current > a', function(e){e.preventDefault(); if(jQuery(window).width()<768){jQuery(e.currentTarget).parent().toggleClass('open');}});</script>
Add in Custom CSS:
.sub-menu {
position: absolute;
top: 100%;
left: 0;
z-index: 1000;
display: none;
float: left;
min-width: 160px;
padding: 5px 0;
margin: 2px 0 0;
font-size: 14px;
text-align: left;
list-style: none;
background-color: #fff;
-webkit-background-clip: padding-box;
background-clip: padding-box;
border: 1px solid #ccc;
border: 1px solid rgba(0,0,0,.15);
border-radius: 4px;
-webkit-box-shadow: 0 6px 12px rgba(0,0,0,.175);
box-shadow: 0 6px 12px rgba(0,0,0,.175);
}
.open > .sub-menu {
display: block;
}
@media (min-width: 768px) {
.navbar-right .sub-menu {
right: 0;
left: auto;
}
}
@media (max-width: 767px) {
.navbar-nav .open .sub-menu {
position: static;
float: none;
width: auto;
margin-top: 0;
background-color: transparent;
border: 0;
-webkit-box-shadow: none;
box-shadow: none;
}
}
.navbar-nav > li > .sub-menu {
margin-top: 0;
border-top-left-radius: 0;
border-top-right-radius: 0;
}

.navbar-default .navbar-nav .menu-item-language-current li > a {
line-height: 28px;
border-bottom: none;
margin-bottom: 0px;
}
.sub-menu > li > a {
display: block;
padding: 3px 20px;
clear: both;
white-space: nowrap;
}
.sub-menu > li > a:hover {
color: #262626;
text-decoration: none;
background-color: #f5f5f5;
}
@media (max-width: 767px) {
.navbar-default .navbar-nav .open .sub-menu > li > a {
color: #777;
}
.navbar-default .navbar-nav .open .sub-menu > li > a:hover {
color: #333;
background-color: transparent;
background-image: none;
}
}
.navbar-default .sub-menu li a {
margin-right: 0;
}
.navbar-default .navbar-nav .active .sub-menu li > a,
.navbar-default .navbar-nav li.current-menu-parent .sub-menu li > a,
.navbar-default .navbar-nav li.current_page_parent .sub-menu li > a,
.navbar-default .navbar-nav .menu-item-language > a {
border-bottom: 0 !important;
}
.navbar-default .navbar-nav ul.sub-menu li > ul.sub-menu {
top: 0;
left: 100%;
margin-top: -6px;
-webkit-border-radius: 0 6px 6px 6px;
-moz-border-radius: 0 6px 6px;
border-radius: 0 6px 6px 6px;
}
.navbar-default .navbar-nav ul.sub-menu li:hover > ul.sub-menu,
ul.sub-menu li:focus > ul.sub-menu {
display: block;
}
ul.nav li.menu-item-language-current > a::after {
display: inline-block;
width: 0;
height: 0;
margin-left: 8px;
vertical-align: middle;
border-top: 4px dashed;
border-right: 4px solid transparent;
border-left: 4px solid transparent;
content: '';
}
@media (min-width: 980px) {
ul.nav li.menu-item-language-current:hover > ul.sub-menu {
display: block;
}
}