Ender dragon flies through walls

I just entered the End for the first time and spawned below ground surrounded by end stone from all directions. the dragon attacked me through obsidian that was below me. after that i started digging a row up (needed to climb about 10-12 block up in the "y" direction) and in the middle of the row i was attacked again. currently there is no way i could hide from him, i get attacked everywhere.

LOL this sound like a crime report