If you don't see the mobile toggle bar on lower resolutions, please follow the steps below:

Step 1: 

Make sure you've activated the Max Mega Menu plugin. The mobile menu in the VamTam Beaver Builder themes is built using the Max Mega Menu plugin, so it won't work without having this plugin activated. You can install and activate the plugin at any time in Dashboard > Appearance > Install Plugins

This is how the mobile menu will look like if the Max Mega Menu plugin isn't activated:

Step 2:

Make sure you are have imported the Menu Themes. If not, you have to set the settings manually, following this guide:

Vamtam Beaver Themes: Guide to Max Mega Menu

Step 3:

The updates are essential as we fix bugs, provide new features and improvements and make the theme compatible with newer WordPress versions. If you notice some issues with your installation, always make sure that you aren't running an old theme version that is not compatible with the latest version of WordPress.

Do not forget to update all your plugins to the latest version,  otherwise, the theme will not function properly. 

You can update your theme and plugins safely following the Update guide.

Step 4:

Make sure that the Max Mega Menu is enabled for the Menu Header:

Step 5:

If you've done all previous steps and it still doesn't work, please deactivate all plugins that don't come with the theme to rule out any third party conflicts.

For more information about the Max Mega Menu plugin please check this article: https://beaver.support.vamtam.com/support/solutions/articles/227265-vamtam-beaver-themes-guide-to-max-mega-menu