title: Why am I getting the error plugin_not_installed with the Ionic Framework plugin healthkit?
body: <p>I have been using Ionic Framework for a while but I have recently come across this error <code>plugin_not_installed</code> for the Health Kit plugin which I know I have based on my <code>ionic cordova plugin list</code> output.</p>
  
  <pre><code>$ ionic cordova plugin list
  &gt; cordova plugin ls
  com.telerik.plugins.healthkit 0.5.5 "HealthKit"
  cordova-plugin-apprate 1.3.0 "AppRate"
  cordova-plugin-badge 0.8.5 "Badge"
  cordova-plugin-device 1.1.4 "Device"
  cordova-plugin-dialogs 1.3.4 "Notification"
  cordova-plugin-globalization 1.0.8 "Globalization"
  cordova-plugin-google-analytics 1.8.3 "Google Universal Analytics Plugin"
  cordova-plugin-inappbrowser 1.7.2 "InAppBrowser"
  cordova-plugin-ionic-webview 1.1.16 "cordova-plugin-ionic-webview"
  cordova-plugin-local-notification 0.9.0-beta.1 "LocalNotification"
  cordova-plugin-splashscreen 4.0.3 "Splashscreen"
  cordova-plugin-statusbar 2.3.0 "StatusBar"
  cordova-plugin-whitelist 1.3.1 "Whitelist"
  ionic-plugin-keyboard 2.2.1 "Keyboard"
  </code></pre>
  
  <p>My code is wrapped in <code>platform.ready()</code> so I know that everything is loaded. I also have my health kit code that is throwing the error in a <code>healthKit.available()</code> and a <code>healthKit.requestAuthorization</code> which have no error.</p>
  
  <pre><code>getWeight.then(function () {
      alert("Healthkit is ready!");
      alert(weight);
      healthKitReady = true;
   }).catch(function(err) {
       if (err) {
           console.log(err); // This is where the error is returned.
       }
    });
  </code></pre>
  
  <p>The function getWeight is this:</p>
  
  <pre><code>const getWeight = new Promise(function(resolve, reject) {
      var error;
      healthKit.readWeight({
          unit: "lb"
      }).then(function (out) {
          weight = Math.round(out.value);
          alert("weight: " + weight);
          resolve(weight);
      }, function (err) {
          error = err;
          reject(error);
      });
  });
  </code></pre>
  
  <p>Just in case this is a version issue this is the output for ionic info:</p>
  
  <pre><code>cli packages: (/usr/local/share/.config/yarn/global/node_modules)
  
      @ionic/cli-utils  : 1.19.0
      ionic (Ionic CLI) : 3.19.0
  
  global packages:
  
      cordova (Cordova CLI) : 7.1.0 
  
  local packages:
  
      @ionic/app-scripts : 3.1.4
      Cordova Platforms  : ios 4.5.4
      Ionic Framework    : ionic-angular 3.9.2
  
  System:
  
      ios-deploy : 1.9.2 
      ios-sim    : 6.1.2 
      Node       : v8.9.1
      npm        : 2.15.12 
      OS         : macOS High Sierra
      Xcode      : Xcode 9.2 Build version 9C40b 
  
  Environment Variables:
  
      ANDROID_HOME : not set
  
  Misc:
  
      backend : pro
  </code></pre>