Since the comment box is at the bottom of the screen when replying to people it will be covered when you open up your keyboard.
I am using a OnePlus 5T.
Similar problem makes it annoying but you can type everything out and then close out the keyboard and reply. Can’t check your work though hahha
@Xevion thank you for letting us know (never imagined of this happening). We’ll look into ways to fix it!