title: IF user_signed in? CASE current_user.plan_id ELSE ...?
body: <p>This 'elegant' helper for showing the user/member status is working perfectly for CASE 1-3 but not working (not showing anything at ERB view &lt;%= user_cat %>) for: </p>
  
  <ul>
  <li>user.plan_id=NULL </li>
  </ul>
  
  <p>What's the error? How to fix it?</p>
  
  <hr>
  
  <pre><code>  def user_cat
      if user_signed_in?
        case current_user.plan_id
        when 1 
          'ESPORÀDIC'
        when 2 
          'FREQÜENT'
        when 3 
          'HABITUAL'
        end 
      else
        'IDENTIFICA\'T'
      end
   end
  </code></pre>
  
  <hr>
  
  <p><em>Ruby 2.64 and Rails 6.0.0</em></p>
  
  <p>Thanks in advance!</p>