Champion being locked when I bought her

So i've had lux for a while, and i recently was gifted elementalist lux for my birthday. Today i queued up for a ranked game, telling myself i wanted to play lux. But when I got into champ select, lux wasnt appearing as an option. After the game, i went to my owned champions, and she wasnt their either. When I would hover over the lux icon, it would say locked, but it said i owned the skin. Anyone know why this is happening?