I was named Bien but people ussuall call me Thuy/ I ussuall is called Thuy
I think, there is a little bit different.And "named" as I was explained once, It is rather literal than formal.
I dont know it for sure. In my opinion,
"is named" is the name which A give it to B. Ex: Child was named by his father.
"is called" is everybody call the name of someone.