Backup not working

Make sure to update and use the latest version of the plugin.

I have the latest version. ??

What is the exact message that you see when you export the website?

That the database export couldn’t be done and that I should try it later. Get this message since days.

OK, in that case usually the database server or PHP server stop working.
What you could do is to access (or request from hosting provider) the error logs of your Webserver, PHP, and MySQL and then look at them to see the exact error message.
It might be because PHP does not have enough memory or something else but instead of guessing, let’s find out the exact error, and then I can guide you on how to fix it.

Same here:

[21-Jan-2022 12:21:59 UTC] PHP Fatal error:  Uncaught TypeError: mysqli_fetch_row(): Argument #1 ($result) must be of type mysqli_result, bool given in /src/wp-content/plugins/all-in-one-wp-migration/lib/vendor/servmask/database/class-ai1wm-database-mys
qli.php:123
Stack trace:
#0 /src/wp-content/plugins/all-in-one-wp-migration/lib/vendor/servmask/database/class-ai1wm-database-mysqli.php(123): mysqli_fetch_row(false)
#1 /src/wp-content/plugins/all-in-one-wp-migration/lib/vendor/servmask/database/class-ai1wm-database.php(707): Ai1wm_Database_Mysqli->fetch_row(false)
#2 /src/wp-content/plugins/all-in-one-wp-migration/lib/vendor/servmask/database/class-ai1wm-database.php(739): Ai1wm_Database->get_base_tables()
#3 /src/wp-content/plugins/all-in-one-wp-migration/lib/model/export/class-ai1wm-export-enumerate-tables.php(77): Ai1wm_Database->get_tables()
#4 /src/wp-content/plugins/all-in-one-wp-migration/lib/controller/class-ai1wm-export-controller.php(70): Ai1wm_Export_Enumerate_Tables::execute(Array)
#5 /src/wp-includes/class-wp-hook.php(303): Ai1wm_Export_Controller::export(Array)
#6 /src/wp-includes/class-wp-hook.php(327): WP_Hook->apply_filters('', Array)
#7 /src/wp-includes/plugin.php(470): WP_Hook->do_action(Array)
#8 /src/wp-admin/admin-ajax.php(187): do_action('wp_ajax_ai1wm_e...')
#9 {main}
  thrown in /src/wp-content/plugins/all-in-one-wp-migration/lib/vendor/servmask/database/class-ai1wm-database-mysqli.php on line 123

@gypsyberlin
Please open your own topic.

Thanks, did it.