[GAMEPLAY Bug] Vieger can't level up?

(As Vieger) There might be a bug where vieger can't gain xp.

I was playing a game on Summoner's Rift, and at one point in the game I noticed I was significantly lower levels in XP than everyone else. I looked at my CS and I had a good CS score as expected for a solo laner in the mid lane. However, I was confused why my levels were so much lower.

I had approximately 4/4/6 - k/d/a with a good CS score, yet my xp level was one less-than my support??? I went mid and cleared a couple waves, then went top and cleared about 3 more waves and it seemed like I wasn't getting the right xp.

I will post the final score in Levels and kda to show how significantly lower I was than everyone else.

My Team Top Lane - Level 18 - 7/11/1 - 306cs Jungle - Level 18 - 5/10/16 - 209cs Mid (me) - Level 16 - 5/8/8 - 208cs Bot - Level 17 - 17/7/5 - 264cs Support - Level 15 - 1/7/21 - 7cs

Enemy Team Top - Level 18 - 5/7/16 Jungle - Level 18 - 12/7/18 Mid - Level 17 - 12/10/10 Bot - Level 18 - 12/5/16 Support - Level 18 - 2/6/28

42 minute game... I was using the Santa Claus skin so if that makes any difference.

I can post the op.gg score if you want.