Disable Using Command Line

php bin/magento config:set admin/captcha/enable 0
php bin/magento cache:flush

Disable Directly in Database

UPDATE core_config_data
SET value = 0
WHERE path = ‘admin/captcha/enable’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/fonts%’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/mode’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/forms%’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/enable%’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/always_for%’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/type%’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/timeout%’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/failed_attempts_logging%’;

DELETE FROM core_config_data WHERE path LIKE ‘admin/captcha/max_attempts%’;