Exception is not being reported to graylog

I'm trying to send exception error logs to graylog but it's not being reported.
Graylog only receives the log when I do:
\Log::{error,debug,info}('MESSAGE HERE');
My graylog configuration: ` 'gelf' => [ 'driver' => 'custom',
        'via' => \Hedii\LaravelGelfLogger\GelfLoggerFactory::class,

        // This optional option determines the processors that should be
        // pushed to the handler. This option is useful to modify a field
        // in the log context (see NullStringProcessor), or to add extra
        // data. Each processor must be a callable or an object with an
        // __invoke method: see monolog documentation about processors.
        // Default is an empty array.
        'processors' => [
            \Hedii\LaravelGelfLogger\Processors\NullStringProcessor::class,
            \Hedii\LaravelGelfLogger\Processors\RenameIdFieldProcessor::class,
            // another processor...
        ],

        // This optional option determines the minimum "level" a message
        // must be in order to be logged by the channel. Default is 'debug'
        'level' => env('LOG_LEVEL', 'debug'),

        // This optional option determines the channel name sent with the
        // message in the 'facility' field. Default is equal to app.env
        // configuration value
        'name' => gethostname(),

        // This optional option determines the system name sent with the
        // message in the 'source' field. When forgotten or set to null,
        // the current hostname is used.
        'system_name' => gethostname(),

        // This optional option determines if you want the UDP, TCP or HTTP
        // transport for the gelf log messages. Default is UDP
        'transport' => 'udp',

        // This optional option determines the host that will receive the
        // gelf log messages. Default is 127.0.0.1
        'host' => env('GRAYLOG_HOST'),

        // This optional option determines the port on which the gelf
        // receiver host is listening. Default is 12201
        'port' => env('GRAYLOG_PORT'),

        // This optional option determines the chunk size used when
        // transferring message via UDP transport. Default is 1420.
        'chunk_size' => 1420,

        // This optional option determines the path used for the HTTP
        // transport. When forgotten or set to null, default path '/gelf'
        // is used.
        'path' => null,

        // This optional option enable or disable ssl on TCP or HTTP
        // transports. Default is false.
        'ssl' => false,

        // If ssl is enabled, the following configuration is used.
        'ssl_options' => [
            // Enable or disable the peer certificate check. Default is
            // true.
            'verify_peer' => true,

            // Path to a custom CA file (eg: "/path/to/ca.pem"). Default
            // is null.
            'ca_file' => null,

            // List of ciphers the SSL layer may use, formatted as
            // specified in ciphers(1). Default is null.
            'ciphers' => null,

            // Whether self-signed certificates are allowed. Default is
            // false.
            'allow_self_signed' => false,
        ],

        // This optional option determines the maximum length per message
        // field. When forgotten or set to null, the default value of
        // \Monolog\Formatter\GelfMessageFormatter::DEFAULT_MAX_LENGTH is
        // used (currently this value is 32766)
        'max_length' => null,

        // This optional option determines the prefix for 'context' fields
        // from the Monolog record. Default is null (no context prefix)
        'context_prefix' => null,

        // This optional option determines the prefix for 'extra' fields
        // from the Monolog record. Default is null (no extra prefix)
        'extra_prefix' => null,

        // This optional option determines whether errors thrown during
        // logging should be ignored or not. Default is true.
        'ignore_error' => false,
    ]
hedii / laravel-gelf-logger

Exception is not being reported to graylog #52
