Thanks Brajesh.

Yes, it is the WooCommerce subscription plugin. This includes an ajax-enabled toggle to automatically renew (or not) a subscription.

On the front end, the plugin adds a subscription tab, which shows a table of subscriptions. If you click to see the details, you get taken to a page (‘view-subscription’) which includes this toggle.

If this page is loaded without the relevant scripts, then the toggle doesn’t work.

I believe the relevant scripts are here:
https://github.com/wp-premium/woocommerce-subscriptions/blob/master/woocommerce-subscriptions.php#L369-L400

As you can see from the extract below, this loads some front-end scripts that I think are not loaded by the BuddyCommerce plugin.

Is there an easy way to add these scripts to the plugin? If you point me in the right direction I can see if I can work it out. Alternatively I’m happy to give you full access to our development site if you want to take a look or experiment.

Here is the code fromm Woocommerce subscriptions that I think is relevant:

 
public static function enqueue_frontend_scripts() {
		$dependencies = array( 'jquery' );

		if ( is_cart() || is_checkout() ) {
			wp_enqueue_script( 'wcs-cart', plugin_dir_url( WC_Subscriptions::$plugin_file ) . 'assets/js/frontend/wcs-cart.js', $dependencies, WC_Subscriptions::$version, true );
		} elseif ( is_product() ) {
			wp_enqueue_script( 'wcs-single-product', plugin_dir_url( WC_Subscriptions::$plugin_file ) . 'assets/js/frontend/single-product.js', $dependencies, WC_Subscriptions::$version, true );
		} elseif ( wcs_is_view_subscription_page() ) {
			global $wp;
			$subscription   = wcs_get_subscription( $wp->query_vars['view-subscription'] );

			if ( $subscription && current_user_can( 'view_order', $subscription->get_id() ) ) {
				$dependencies[] = 'jquery-blockui';
				$script_params  = array(
					'ajax_url'               => esc_url( WC()->ajax_url() ),
					'subscription_id'        => $subscription->get_id(),
					'add_payment_method_msg' => __( 'To enable automatic renewals for this subscription, you will first need to add a payment method.', 'woocommerce-subscriptions' ) . "\n\n" . __( 'Would you like to add a payment method now?', 'woocommerce-subscriptions' ),
					'auto_renew_nonce'       => WCS_My_Account_Auto_Renew_Toggle::can_user_toggle_auto_renewal( $subscription ) ? wp_create_nonce( "toggle-auto-renew-{$subscription->get_id()}" ) : false,
					'add_payment_method_url' => esc_url( $subscription->get_change_payment_method_url() ),
					'has_payment_gateway'    => $subscription->has_payment_gateway() && wc_get_payment_gateway_by_order( $subscription )->supports( 'subscriptions' ),
				);
				wp_enqueue_script( 'wcs-view-subscription', plugin_dir_url( WC_Subscriptions::$plugin_file ) . 'assets/js/frontend/view-subscription.js', $dependencies, WC_Subscriptions::$version, true );
				wp_localize_script( 'wcs-view-subscription', 'WCSViewSubscription', apply_filters( 'woocommerce_subscriptions_frontend_view_subscription_script_parameters', $script_params ) );
			}
		}
	}