From the image, it looks like an over growth of the keratin.
I know when we damage our nails, a few weeks or months down the line the new nail can grow back in a weird way, sometimes pointing upwards.
Maybe she caught, knocked or damaged the top of her beak and when it's grown, it's come in like that.
It's hard to know for sure without having an actual look.
If it was my bird and it felt exactly like the beak itself, I'd keep an eye on it. If it doesn't grow anymore, I'd leave it. If it continues to grow, I'd slowly and carefully file it down. If it bleeds, I wouldn't carry on.