title: Heroku app uploads only once w/ AWS S3 security credentials
body: <p>Heroku app gives a error message to have a look at the logs and <code>heroku logs --tail</code> shows 401 error or writes simply "idle" when uploading a file to amazon S3. Once I have seen SQL statement for inserting file into MariaDB. What's this all about?</p>
  
  <p>I changed the AWS S3 security credentials, both in AWS console and in my heroku environment. Then the upload works for one single time.</p>
  
  <p>Expected: AWS S3 upload works permanently.</p>
  
  <p>Actual: file gets uploaded only once.</p>
  
  <pre><code>leder@DESKTOP-M6L5EDG:~$ ruby -v
  ruby 2.5.1p57 (2018-03-29 revision 63029) [x86_64-linux]
  leder@DESKTOP-M6L5EDG:~$ rails -v
  Rails 5.1.2
  leder@DESKTOP-M6L5EDG:~$
  </code></pre>