src/de/steamwar/bungeecore/commands/TeamCommand.java

@@ -255,7 +255,7 @@ public class TeamCommand extends BasicCommand {
         user.setTeam(0);
 
         if(user.isLeader() && team.size() > 0){
-            team.disband();
+            team.disband(user);
         }
 
         Message.send("TEAM_LEAVE_LEFT", player);

src/de/steamwar/bungeecore/sql/Team.java

@@ -154,8 +154,9 @@ public class Team {
         }
     }
 
-    public void disband(){
-        SQL.update("UPDATE Team SET TeamDeleted = 1, TeamLeader = NULL WHERE TeamID = ?", teamId);
+    public void disband(SteamwarUser user){
+        user.setLeader(false);
+        SQL.update("UPDATE Team SET TeamDeleted = 1", teamId);
         teamCache.remove(this);
     }