Update Errors: Missing Table

Hi Andrey Plechev and Team!

My WP version: 5.4.1
My WP-Recall version: 16.18.10 installed. (Update to 16.18.20).

Incident #1: When I installed update v16.18.20, all my old settings and chats lost i.e. it was back to fresh install.

Incident #2: I uninstall v16.18.20, and reinstall the old version 16.18.10. All the previous settings are back, but all the data was lost.

Error Message:
WordPress database error Table ‘db1.table1_rcl_chat_messages’ doesn’t exist for query SELECT t.* FROM ( SELECT chat_messages.* FROM table1_rcl_chat_messages AS chat_messages INNER JOIN table1_rcl_chat_users AS chat_users ON chat_messages.chat_id=chat_users.chat_id WHERE chat_messages.private_key!=’0′ AND (chat_messages.user_id=’18’ OR chat_messages.private_key=’18’) AND chat_users.user_id=’18’ AND chat_users.user_status!=’0′ ORDER BY chat_messages.message_time DESC LIMIT 18446744073709551615 ) AS t GROUP BY t.chat_id ORDER BY t.message_time DESC LIMIT 0,5 made by require(‘wp-blog-header.php’), require_once(‘wp-includes/template-loader.php’), include(‘/themes/tutor/page.php’), get_footer, locate_template, load_template, require_once(‘/themes/cisc-homework-subsite-classrooms-tutor-child/footer.php’), wp_footer, do_action(‘wp_footer’), WP_Hook->do_action, WP_Hook->apply_filters, rcl_get_last_chats_box, rcl_get_user_contacts

Question 1:
How to prevent this kind of incidents happening for the future WP Recall updates?

Question 2:
Any advice to the lost the data?

Best regards,

Mike

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