1. Check the error log for the MySQL 143 error:

$ tail -f /var/log/mysql/error.log

2. Check the MySQL configuration file for any misconfigurations:

$ cat /etc/mysql/my.cnf

3. Check the MySQL process list to see if any processes are running that shouldn't be:

$ mysqladmin -u root -p processlist

4. Check the MySQL user table to see if any users have been added that shouldn't be:

$ mysql -u root -p -e "SELECT User, Host FROM mysql.user;"

5. Check the MySQL database tables to see if any tables have been added that shouldn't be:

$ mysql -u root -p -e "SHOW TABLES;"

6. Restart the MySQL service to apply any changes:

$ service mysql restart

7. Use an automated database observability tool to monitor and fix the MySQL 143 in question. Automated database observability tools can provide real-time visibility into the performance and health of your database, allowing you to quickly identify and fix any issues that may arise. They can also provide detailed insights into the root cause of any issues, allowing you to take proactive steps to prevent them from occurring in the future.