title: Uber OAuth authorization Error: error.invalid_request by using R's "ubeR" package
body: <p>I tried to simply use R to estimate the trip cost between 2 places using Uber. I carefully followed each step on <a href="https://www.rdocumentation.org/packages/ubeR/versions/0.1.4" rel="nofollow noreferrer">https://www.rdocumentation.org/packages/ubeR/versions/0.1.4</a>. </p>
  
  <p>After I created a new app in Uber Developer, I copied the client ID and client secret to R using <code>uber_oauth(UBER_CLIENTID, UBER_CLIENTSECRET)</code>, then an authentication page in browser popped up. I entered my account information and I am 100% sure they were correct, but then the Uber webpage showed </p>
  
  <blockquote>
    <p>"Authorization Error: error.invalid_request".</p>
  </blockquote>
  
  <p>I am not a computer engineer so I don't know much about app development. Does anyone who used <code>ubeR</code> package in R before know how to solve this problem?</p>
  
  <p>I tried created 3 different apps and tried 2 browsers, but neither helped.</p>