Fatal errors on Call to member

This plugin has been throwing errors on my client’s site and I finally had to disable it because anytime we try to create a coupon, we get a fatal error associated wtiht Share a Sale tracker plugin. What can be done to remedy this?

Here’s just ONE Of many in the error logs:

1 PHP Fatal error:  Uncaught Error: Call to a member function get_meta() on bool in /nas/content/live/leafpeople/wp-content/plugins/shareasale-wc-tracker/admin/class-shareasale-wc-tracker-admin.php:125\nStack trace:\n#0 /nas/content/live/leafpeople/wp-includes/class-wp-hook.php(324): ShareASale_WC_Tracker_Admin->woocommerce_coupon_options_save(81230, Object(WC_Coupon))\n#1 /nas/content/live/leafpeople/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters('', Array)\n#2 /nas/content/live/leafpeople/wp-includes/plugin.php(517): WP_Hook->do_action(Array)\n#3 /nas/content/live/leafpeople/wp-content/plugins/woocommerce/includes/admin/meta-boxes/class-wc-meta-box-coupon-data.php(392): do_action('woocommerce_cou...', 81230, Object(WC_Coupon))\n#4 /nas/content/live/leafpeople/wp-includes/class-wp-hook.php(324): WC_Meta_Box_Coupon_Data::save(81230, Object(WP_Post))\n#5 /nas/content/live/leafpeople/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters('', Array)\n#6 /nas/content/live/leafpeople/wp-includes/plugin.php(517): WP_Hook->do_action(Array)\n#7 /nas/content/live/leafpeople/wp-content/plugins/woocommerce/includes/admin/class-wc-admin-meta-boxes.php(273): do_action('woocommerce_pro...', 81230, Object(WP_Post))\n#8 /nas/content/live/leafpeople/wp-includes/class-wp-hook.php(326): WC_Admin_Meta_Boxes->save_meta_boxes(81230, Object(WP_Post))\n#9 /nas/content/live/leafpeople/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(NULL, Array)\n#10 /nas/content/live/leafpeople/wp-includes/plugin.php(517): WP_Hook->do_action(Array)\n#11 /nas/content/live/leafpeople/wp-includes/post.php(4828): do_action('save_post', 81230, Object(WP_Post), true)\n#12 /nas/content/live/leafpeople/wp-includes/post.php(4930): wp_insert_post(Array, false, true)\n#13 /nas/content/live/leafpeople/wp-admin/includes/post.php(453): wp_update_post(Array)\n#14 /nas/content/live/leafpeople/wp-admin/post.php(227): edit_post()\n#15 {main}\n  thrown in /nas/content/live/leafpeople/wp-content/plugins/shareasale-wc-tracker/admin/class-shareasale-wc-tracker-admin.php on line 125, referer: https://leafpeople.com/wp-admin/post.php?post=81230&action=edit

The page I need help with: [log in to see the link]