Getting various php fatal errors with elasticpress

I try to build Elastic Search indexes, but getting various php fatal errors in the output
wp elasticpress index –setup
Success: Index deleted
Success: Mapping sent
Indexing posts…
PHP Fatal error: Uncaught Error: Call to a member function get_value() on null in /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/themes/flatsome/inc/woocommerce/structure-wc-product-box.php:8
Stack trace:
#0 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-includes/class-wp-hook.php(298): flatsome_sale_flash(”, Object(WP_Post), Object(WC_Product_Variable), ‘circle’)
#1 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-includes/plugin.php(203): WP_Hook->apply_filters(”, Array)
#2 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/themes/flatsome/woocommerce/loop/sale-flash.php(43): apply_filters(‘flatsome_produc…’, ”, Object(WP_Post), Object(WC_Product_Variable), ‘circle’)
#3 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/plugins/woocommerce/includes/wc-core-functions.php(205): include(‘/home/112253.cl…’)
#4 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/plugins/woocommerce/includes/wc-template-functions.php(778): wc_get_template(‘loop/sa in /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/themes/flatsome/inc/woocommerce/structure-wc-product-box.php on line 8
Fatal error: Uncaught Error: Call to a member function get_value() on null in /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/themes/flatsome/inc/woocommerce/structure-wc-product-box.php:8
Stack trace:
#0 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-includes/class-wp-hook.php(298): flatsome_sale_flash(”, Object(WP_Post), Object(WC_Product_Variable), ‘circle’)
#1 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-includes/plugin.php(203): WP_Hook->apply_filters(”, Array)
#2 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/themes/flatsome/woocommerce/loop/sale-flash.php(43): apply_filters(‘flatsome_produc…’, ”, Object(WP_Post), Object(WC_Product_Variable), ‘circle’)
#3 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/plugins/woocommerce/includes/wc-core-functions.php(205): include(‘/home/112253.cl…’)
#4 /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/plugins/woocommerce/includes/wc-template-functions.php(778): wc_get_template(‘loop/sa in /home/112253.cloudwaysapps.com/pgserwjutd/public_html/wp-content/themes/flatsome/inc/woocommerce/structure-wc-product-box.php on line 8
Adding mapping…
Deleting index…
<p class=”lead shortcode-error text-center”>Sorry, no pages was found</p><p class=”lead shortcode-error text-center”>Sorry, no pages was found</p><p class=”lead shortcode-error text-center”>Sorry, no pages was found</p>