How to delete a player's result if he "departed" from the rating?

Question

Windows Forms

I need to make sure that the player is removed from the dictionary and from the file, if he "flies" out of the rating (i.e. takes 6th place)
here is the code for sorting them in places, maybe it will help with something:

private void updateRatingLabels() {
   var tops = AllNames()
     .OrderBy(pair => pair.Value)                      
     .ThenBy(pair => pair.Key, StringComparer.Ordinal) 
     .Take(5)                                          
     .ToArray();
 
   
   for (int i = 18; i <= 22; ++i)
     Controls.Find($"label{i}", true).First().Text = "";
 
   for (int i = 28; i <= 32; ++i)
     Controls.Find($"label{i}", true).First().Text = "";
 
   
   for (int i = 0; i < tops.Length; ++i) {
     Controls.Find($"label{i + 18}", true).First().Text = tops[i].Key;
     Controls.Find($"label{i + 28}", true).First().Text = tops[i].Value.ToString();
   }
 }