FTP upload file failed in Docker container

I have a spring boot app using library apache commons-net<br/>
I have a FTP server running on AWS EC2.<br/>
Filezilla connect and upload file normally.<br/>
Local app connect and upload file normally.<br/>
When i run this app using Docker, the app connect to ftp succeed,but it cannot upload file.<br/>
Reply code is: 500<br/><br/>
Dockerfile:

FROM openjdk:11
RUN mkdir /app
COPY build/libs/aws-batch1-1.0.0.jar /app/aws-batch1.jar
ENTRYPOINT ["java","-jar","/app/aws-batch1.jar","Test"]

Image build command:

docker build -t aws-batch1 .

Image run command:

docker run aws-batch1

Code connect FTP:

private boolean connectFTPServer() throws IOException {
        LOGGER.info("CONNECT");
        boolean flg = true;
        try {
            ftpClient.connect(FTP_SERVER_ADDRESS, FTP_SERVER_PORT_NUMBER);
            ftpClient.login(FTP_USERNAME, FTP_PASSWORD);
        } catch (IOException e) {
            LOGGER.error("CONNECT FAILED", e);
            flg = false;
        }

        int replyCode = ftpClient.getReplyCode();
        LOGGER.info("replyCode: " + replyCode);
        if (!FTPReply.isPositiveCompletion(replyCode)) {
            flg = false;
        }
        if (!flg) {
            throw new IOException();
        }
        return flg;
    }

Code upload file:

public boolean uploadFile(byte[] content, String fileName)
            throws IOException {
        boolean flg = false;
        LOGGER.info("uploadFile");
        if (connectFTPServer()) {
            LOGGER.info("connectFTPServer success");
            LOGGER.info("content: " + new String(content));
            try (InputStream is = new ByteArrayInputStream(content)) {
                ftpClient.setFileType(FTP.BINARY_FILE_TYPE);
                boolean storeFile = ftpClient.storeFile(fileName, is);
                LOGGER.info("storeFile: " + storeFile);
                LOGGER.info("ftpClient.getReplyCode(): " + ftpClient.getReplyCode());

                flg = storeFile &&
                        ftpClient.getReplyCode() ==
                                FTPReply.CLOSING_DATA_CONNECTION;
                if (!flg) {
                    throw new IOException("FTP error");
                }
            } finally {
                closeConnectionFTPClient();
            }
        }
        return flg;
    }

Log when upload on local successful:

uploadFile
CONNECT
replyCode: 230
connectFTPServer success
content: test
storeFile: true
ftpClient.getReplyCode(): 226

Log when upload on Docker failed:

uploadFile
CONNECT
replyCode: 230
connectFTPServer success
content: test
storeFile: false
ftpClient.getReplyCode(): 500

Please help me. Am I missing any steps?

UPDATE:Thanks @Metin
I have updated the code to connect to ftp client as below:

private boolean connectFTPServer() throws IOException {
        LOGGER.info("CONNECT");
        boolean flg = true;
        try {
            ftpClient.connect(FTP_SERVER_ADDRESS, FTP_SERVER_PORT_NUMBER);
            ftpClient.login(FTP_USERNAME, FTP_PASSWORD);
            ftpClient.enterLocalPassiveMode();
        } catch (IOException e) {
            LOGGER.error("CONNECT FAILED", e);
            flg = false;
        }

        int replyCode = ftpClient.getReplyCode();
        LOGGER.info("replyCode: " + replyCode);
        if (!FTPReply.isPositiveCompletion(replyCode)) {
            flg = false;
        }
        if (!flg) {
            throw new IOException();
        }
        return flg;
    }

and it works!

You might want to read about the differences of active and passive mode ftp: https://stackoverflow.com/questions/1699145/what-is-the-difference-between-active-and-passive-ftp

You should come to the conclusion that active mode ftp is not suited for containerized ftp clients, due to the nature that the server activily tries to initate a data connection to the ftp client, which is not possible for a container (unless the container uses network: host, which is typicaly unwanted).

With passive mode ftp on the other hand, the server will tell your ftp client which port needs to be used for the next data connection.