DataSource created via console fails when test connection is done in WildFly 9

Unexpected HTTP response: 500

Request
{
    "address" => [
        ("subsystem" => "datasources"),
        ("data-source" => "MySqlDS")
    ],
    "operation" => "test-connection-in-pool"
}

Response

Internal Server Error
{
    "outcome" => "failed",
    "failure-description" => "WFLYJCA0040: failed to invoke operation: WFLYJCA0042: failed to match pool. Check JndiName: java:/MySqlDS",
    "rolled-back" => true,
    "response-headers" => {"process-state" => "reload-required"}
}