exception

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Galaxy Grand Prime Plus (grandpplte)	22
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Galaxy Grand Prime Plus (grandpplte)	22	55.0%
Galaxy J3 Pro (j3xproltechn)	11	27.5%
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K5 Plus (A6020a46)	1	2.5%
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Today, 7:02 PM on app version 5
Samsung Galaxy Grand Prime Plus (grandpplte), Android 6.0
Report 1

java.lang.RuntimeException:
  at android.os.AsyncTask$3.done (AsyncTask.java:309)
  at java.util.concurrent.FutureTask.finishCompletion (FutureTask.java:354)
  at java.util.concurrent.FutureTask.setException (FutureTask.java:223)
  at java.util.concurrent.FutureTask.run (FutureTask.java:242)
  at android.os.AsyncTask$SerialExecutor$1.run (AsyncTask.java:234)
  at java.util.concurrent.ThreadPoolExecutor.runWorker (ThreadPoolExecutor.java:1113)
  at java.util.concurrent.ThreadPoolExecutor$Worker.run (ThreadPoolExecutor.java:588)
  at java.lang.Thread.run (Thread.java:818)
Caused by: java.lang.NullPointerException:
  at org.apache.commons.net.ftp.FTP.sendCommand (FTP.java:441)
  at org.apache.commons.net.ftp.FTP.sendCommand (FTP.java:520)
  at org.apache.commons.net.ftp.FTP.sendCommand (FTP.java:569)
  at org.apache.commons.net.ftp.FTP.quit (FTP.java:781)
  at org.apache.commons.net.ftp.FTPClient.logout (FTPClient.java:706)
  at id.pptik.siwaslupublic.Helpers.FileTransfer.downloadAndSaveFile (FileTransfer.java:223)
  at id.pptik.siwaslupublic.Helpers.DownloadFile.doInBackground (DownloadFile.java:51)
  at id.pptik.siwaslupublic.Helpers.DownloadFile.doInBackground (DownloadFile.java:18)
  at android.os.AsyncTask$2.call (AsyncTask.java:295)
  at java.util.concurrent.FutureTask.run (FutureTask.java:237)