Glitches happen with Ender Dragon when summoned in the normal world

Steps to Reproduce

1.In Survival Mode you must summon the Ender Dragon
2. Sometimes after summoning it you will see that it will only push you and not attack you and also other mobs. After it will only go in one direction and will not come back
3. Sometimes when he is in the normal world, he goes to earth and makes a hole that goes up to bedrock and after leaving he goes back to the same hole and does it repeatedly