Lava lakes spawning under aquafers below y=0

The lava lakes are spawning under water without converting into obsidian below y=0. I have attached images and some axolotls too for showing it's underwater. When I tried to scoop lava into buckets from middle of the lake nothing happened but when I repeated the same from the edge, the block updated and then converted surface lava to obsidian. Please try fixing it! Thank you