Lava and Sea Grass turned Blue after taking off RTX Texture Pack

Me and my little brother were playing on a vanilla world with and RTX supporting texture pack. I decided to take the RTX texture pack off and then the lava in the cave turned dark blue. We then went to a different world and in there the sea grass had the same dark blue texture all over it. The bug also happened on the Xbox One my little brother was playing on. The bug only happens when I get to about within 10 blocks of it.