预设职级为K1的时候，空指针问题

AppStart/Helper/AlipayPayBack2Service.cs

@@ -1298,12 +1298,12 @@ namespace MySystem
             LeaderRankWhite rank = db.LeaderRankWhite.FirstOrDefault(m => m.Id == UserId);
             if(rank == null)
             {
-                db.LeaderRankWhite.Add(new LeaderRankWhite()
+                rank = db.LeaderRankWhite.Add(new LeaderRankWhite()
                 {
                     CreateDate = DateTime.Now, //设置时间
                     UserId = UserId, //用户
                     Id = UserId,
-                });
+                }).Entity;
                 db.SaveChanges();
             }
             rank.Rank = Rank;