There are 2 ways to customize it:

1. Using Yoast Seo plugin: You can click on Plugins -> Add New -> Install Yoast SEO plugin. When this plugin is enabled, the plugin’s breadcrumb will be used instead of Dokan’s Breadcrumb.
2. Put the following code to functions.php of Wilcity Child Theme

add_filter('woocommerce_get_breadcrumb', function($crumbs){
	if ( !function_exists('dokan_is_store_page') || ! dokan_is_store_page() ) {
		return $crumbs;
	}

	if ( function_exists( 'yoast_breadcrumb' ) && WPSEO_Options::get( 'breadcrumbs-enable' ) ) {
		unset( $crumbs );
		return;
	}

	$custom_store_url = dokan_get_option( 'custom_store_url', 'dokan_general', 'store' );
	$author      = get_query_var( $custom_store_url );
	$seller_info = get_user_by( 'slug', $author );

	$crumbs[1]   = array( ucwords($custom_store_url) , site_url().'/'.$custom_store_url );
	$crumbs[2]   = array( $seller_info->display_name, dokan_get_store_url( $seller_info->data->ID ) );

	return $crumbs;

}, 999);