The?Backup?failed during migration stage – WP-Migrate 2.6.11 WordPress 6.6.1

Error while attempting backup: “The?Backup?failed during the migration initialization stage. An unknown error occurred. Please check your PHP error log or contact support. “

You won’t be able to link to the page. It is a secure internal development site. I have used WP-Migrate on this before without problems but – just need any suggestions what may be the cause of these debug.log errors:

[06-Sep-2024 19:57:32 UTC] PHP Warning: Undefined array key “form_data” in /var/www/html/wp-content/plugins/wp-migrate-db/class/Common/Migration/MigrationManager.php on line 457
[06-Sep-2024 19:57:32 UTC] PHP Deprecated: json_decode(): Passing null to parameter #1 ($json) of type string is deprecated in /var/www/html/wp-content/plugins/wp-migrate-db/class/Common/FormData/FormData.php on line 171
[06-Sep-2024 19:57:32 UTC] PHP Fatal error: Uncaught TypeError: array_intersect_key(): Argument #1 ($array) must be of type array, null given in /var/www/html/wp-content/plugins/wp-migrate-db/class/Common/FormData/FormData.php:175
Stack trace: 0 /var/www/html/wp-content/plugins/wp-migrate-db/class/Common/FormData/FormData.php(175): array_intersect_key(NULL, Array) 1 /var/www/html/wp-content/plugins/wp-migrate-db/class/Common/Migration/MigrationManager.php(457): DeliciousBrains\WPMDB\Common\FormData\FormData->parse_and_save_migration_form_data(NULL) 2 /var/www/html/wp-content/plugins/wp-migrate-db/class/Common/Migration/MigrationManager.php(437): DeliciousBrains\WPMDB\Common\Migration\MigrationManager->ajax_cancel_migration() 3 /var/www/html/wp-includes/rest-api/class-wp-rest-server.php(1230): DeliciousBrains\WPMDB\Common\Migration\MigrationManager->error_migration(Object(WP_REST_Request)) 4 /var/www/html/wp-includes/rest-api/class-wp-rest-server.php(1063): WP_REST_Server->respond_to_request(Object(WP_REST_Request), ‘/mdb-api/v1/err…’, Array, NULL) 5 /var/www/html/wp-includes/rest-api/class-wp-rest-server.php(439): WP_REST_Server->dispatch(Object(WP_REST_Request)) 6 /var/www/html/wp-includes/rest-api.php(420): WP_REST_Server->serve_request(‘/mdb-api/v1/err…’) 7 /var/www/html/wp-includes/class-wp-hook.php(324): rest_api_loaded(Object(WP)) 8 /var/www/html/wp-includes/class-wp-hook.php(348): WP_Hook->apply_filters(”, Array) 9 /var/www/html/wp-includes/plugin.php(565): WP_Hook->do_action(Array) 10 /var/www/html/wp-includes/class-wp.php(418): do_action_ref_array(‘parse_request’, Array) 11 /var/www/html/wp-includes/class-wp.php(813): WP->parse_request(”) 12 /var/www/html/wp-includes/functions.php(1336): WP->main(”) 13 /var/www/html/wp-blog-header.php(16): wp() 14 /var/www/html/index.php(17): require(‘/var/www/html/w…’) 15 {main}

thrown in /var/www/html/wp-content/plugins/wp-migrate-db/class/Common/FormData/FormData.php on line 175