Hi,
It is most likely because the wrapper element, in which the search is placed in the theme, has a bottom property set to -59px on mobile views, so the search bar is ‘cut off’.
Try this custom CSS:
[html]@media only screen and (max-width: 767px) {
.mobile-header-mini #Top_bar .search_wrapper {
top: 0px !important;
bottom: auto !important;
}
}[/html]
Please note that this is outside of the scope of the plugin, so I cannot guarantee that my solution will work.