[MC-155739] Crash when opening the game in the ender dragon boss fight (java.lang.NullPointerException: Colliding entity with block)

So i was fighting the ender dragon and when i finally killed it when i went to take the exp , it crashed , i was kinda mad that i lost the exp but after entering the world again it was low hp so i killed it again and same thing , i tried to see if it was a mod or something but i deactivate all the mods and used a clean version on the game, the latest release (i was playing with mods in 1.14.3 if i confused you ), so after killing it again and crashed , the next time i tried to go in (i did this because the view crash report did not open so i was trying to crash it again so i could see why , and this time i entered and it directly crashed and i was finally able to see why

1.14.3: crash-2019-07-01_00.29.17-server.txt

Description: Colliding entity with block

java.lang.NullPointerException: Colliding entity with block
	at ail.a(SourceFile:2249)
	at boh.a(SourceFile:41)
	at bvo.a(SourceFile:273)
	at ail.al(SourceFile:916)
	at ail.a(SourceFile:622)
	at aiu.e(SourceFile:1961)
	at aiu.k(SourceFile:2296)
	at aiv.k(SourceFile:487)
	at aun.k(SourceFile:39)
	at aud.k(SourceFile:208)
	at aiu.h(SourceFile:2111)
	at aiv.h(SourceFile:294)
	at aun.h(SourceFile:51)
	at vi.a(SourceFile:580)
	at vi$$Lambda$2811/992198863.accept(Unknown Source)
	at bhm.a(SourceFile:676)
	at vi.a(SourceFile:383)
	at net.minecraft.server.MinecraftServer.b(SourceFile:824)
	at net.minecraft.server.MinecraftServer.a(SourceFile:763)
	at dxo.a(SourceFile:128)
	at net.minecraft.server.MinecraftServer.run(SourceFile:631)
	at java.lang.Thread.run(Thread.java:745)