FTP List Contents fails randomly

Hi, Im using Lumen v6.3.3

I have an scheduled job that lists contents of ftp and compares with local and then downloads it;

it Runs code:

Storage::disk('ftp')->listContents('/');

This error occurs on local dev and on remote dev server.

Error: {main} {"exception":"[object] (ErrorException(code: 0): implode(): Invalid arguments passed at backend/vendor/league/flysystem/src/Adapter/Ftp.php:572)

Problem seems to originate from this part of code:

private function getRawExecResponseCode($command)
    {
        $response = @ftp_raw($this->connection, trim($command));

        return (int) preg_replace('/\D/', '', implode(' ', $response));
    }

Q: How can I get logs from FTP commands?