"Sticky Right Sidebar Menu" – not staying sticky

Hello team Kriesi. On the “Enfold Child Theme Options” >> “General Layout”, I choose “Right Sidebar”, but the Menu is not Sticky and there is no option to make it sticky, just like “Left Sidebar”. I found this code on the forum, but it’s not working for me. The submenu it’s shown as “Left Sidebar”. Can you help me with a code that will actual work for the sticky Right sidebar Menu ?

 .html_header_sidebar #top #header.av_always_sticky {
    right: 0;
}

.html_header_left #main {
    margin-left: 0;
    margin-right:300px
}

.html_header_sidebar #header .av-main-nav {
    text-align: right;
}
  
}

Thanks in advance.