iPad Pro 11” hairline crack

Purchased my iPad Pro 11” about 4 months ago. A few weeks back, i noriced a hairline scratch to the right pf the camera. I have no idea what could have caused it because I cared for this iPad very well (hard case and all). It hasn’t dropped and nor has anything dropped on it. I understand that repairs can be pretty pricey but I’m sure I’m still under warranty. And the crack appears to have been spontaneous. How do I go about this? I don’t want to wait until the crack splits the screen in half as I need this device for schoolwork and figure a smaller crack is easier to deal with than a fissure.

My previous 3rd Gen iPad had faced so much more abuse and is physically in pristine condition.