getting error in error_log in root for wp smash and Dashboard

Getting this error in error_log in root of site mentioning

[02-Sep-2016 00:45:14 UTC] WordPress database error Not unique table/alias: 'wp_postmeta' for query SELECT wp_posts.ID FROM wp_posts INNER JOIN wp_postmeta ON ( wp_posts.ID = wp_postmeta.post_id ) LEFT JOIN wp_postmeta ON wp_posts.ID = wp_postmeta.post_id WHERE 1=1 AND (wp_posts.post_mime_type = 'image/jpg' OR wp_posts.post_mime_type = 'image/jpeg' OR wp_posts.post_mime_type = 'image/gif' OR wp_posts.post_mime_type = 'image/png') AND (
wp_postmeta.meta_key = 'wp-smpro-smush-data'
) AND wp_posts.post_type = 'attachment' AND ((wp_posts.post_status = 'inherit')) AND post_date > '2014-06-25 00:00:00' AND post_date < '2016-08-03 23:59:59' AND (wp_postmeta.meta_key = 'snapPN' AND wp_postmeta.meta_value LIKE '%nxsi0pn%') GROUP BY wp_posts.ID ORDER BY wp_posts.post_date ASC made by do_action_ref_array, call_user_func_array, WPMUDEV_Dashboard_Api->refresh_membership_data, apply_filters('wpmudev_api_project_extra_data-912164'), call_user_func_array, WpSmush->send_smush_stats, WpSmushitAdmin->global_stats_from_ids, WpSmushStats->smushed_count, WP_Query->__construct, WP_Query->query, WP_Query->get_posts

this started Aug 24th
Got the error in the log on 24th, 26th, 30th and Sept 2nd