Sometimes, you want to reset all customizer options after you playing with the theme options. To do that, you need to install Customizer Reset plugin. Install the plugin like you install other WordPress plugins and activate the plugin. This plugin will reset theme customizations made via WordPress Customizer by adding a Reset button in the Customizer.
Note: This is not reversible. Once you reset theme modifications, you can’t go back. You will need to redo all modifications from scratch.