title: Can't subset column despite columns are in dataframe
body: <p>I have this code:</p>
  <pre><code>    drugs_from_samples = read_excel(&quot;/Downloads/drugs from samples.xlsx&quot;) %&gt;% 
         dplyr::select(&quot;drug&quot;, &quot;Indication reviewed&quot;, &quot;Action reviewed&quot;, &quot;frequency&quot;)
  </code></pre>
  <p>which results in:
  <a href="https://i.stack.imgur.com/pRb7P.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/pRb7P.png" alt="enter image description here" /></a></p>
  <p>Then, when I try to</p>
  <pre><code>df = drugs_from_samples %&gt;% 
    dplyr::select(-drug) %&gt;% 
    group_by(`Indication reviewed`, `Action reviewed`) %&gt;% 
    summarise(n = sum(frequency))
  
  
  PieDonut(df,
           aes(df$`Indication reviewed`, df$`Action reviewed`, count = n))
  </code></pre>
  <p>When I try to plot the PieDonut, it gives me the error that:</p>
  <blockquote>
  <p>&quot;Can't subset columns that don't exist. x Columns
  df$`Indicationreviewed` and df$`Actionreviewed`` don't
  exist&quot;</p>
  </blockquote>
  <p>I already looked for answers for this specific problems, can anybody give any help?</p>