/kill @e [Distance=50] reports no entities found despite there are two Ender Dragons right there.

the bug is actually for 1.20.5 but the system would not allow me to input that version

 

In creative mode, I used the command /summon and chose the Ender Dragon option so it could clear an area for me. I accidentally summoned two of them to the location.

 

However, when I go to kill them using a command after the area has been

 

I did /kill @e {{_[distance=50,_ type=!player] }}

 

but I got "no entities found" despite the fact that there are TWO Ender Dragons right by me and they are definitely within 50 blocks. 50 blocks is quite a ways. and the two Ender dragons are just above me.

 

It seems that the kill @e cannot find these two Ender Dragons for some reason.