Leveling Up Bug

I currently play league on a daily basis, and I have no life, go ahead, say it. And, each time I level up, after the rank of I believe it was 51, I would have to redo the leveling up from the last stop I made in my recent level, if that makes any sense. Let me make this a bit more clear.

I level up, to let's say, level 54. When I get into my first game at level 54, I level up to level 54 again, because I had to redo that last bit of progress that I had, so basically when I level up, I lose XP.