MySql Connector/Net is not working properly. The team working on bugs is only 3 people and they do not resolve complex issues. There are still unresolved issues from 2009. I
There is now a community-developed open-source .NET connection library for MySQL: https://github.com/mysql-net/MySqlConnector.
It provides true async I/O (for high scalability) and fixes many bugs in Oracle's Connector/NET.