title: Game Center achievements are rewarded every time
body: <p>I am adding achievements into an xCode project. The code below that I am using works fine in awarding the achievement but the only problem is that it is constantly being awarded in the background in the debug console. This is happening every time I load the game.</p>
  
  <p>I also find that when the achievement is awarded for the very first time the completion banner is on repeat.</p>
  
  <p>My question today is how do I edit the code to only award the achievement once, display the banner and then never appear again?</p>
  
  <pre><code>-(void)Scoring
  {
      ScoreNumber = ScoreNumber + AddedScore;
      AddedScore = AddedScore - 1;
  
      if (AddedScore &lt; 0) {
          AddedScore = 0;
      }
  
      Score.text = [NSString stringWithFormat:@"%i", ScoreNumber];
  
      if (ScoreNumber &gt; 110 &amp;&amp; ScoreNumber &lt; 1000) {
          LevelNUmber = 2;
          //self.view.backgroundColor = [UIColor greenColor];
          GKAchievement *achievement= [[GKAchievement alloc] initWithIdentifier:@"_level1easy"];
          achievement.percentComplete = 100.0;
          achievement.showsCompletionBanner = YES;
          if(achievement!= NULL)
              {
                  NSArray *achievements = [NSArray arrayWithObjects:achievement, nil];
                  [GKAchievement reportAchievements:achievements withCompletionHandler:^(NSError *error) {
                      if (error != nil) {
                          NSLog(@"Error in reporting achievements: %@", error);
                      } else {
                          NSLog(@"Achievement 1 Success");
                          }
                  }];
              }
          }
  </code></pre>