[racket] how can I change only one element in the vector?

hello
from the following code, I expected
'#(#(#("2" "2" "3") #("1" "2" "3")) #(#("1" "2" "3") #("1" "2" "3")))
but
the interpreter pop the
'#(#(#("2" "2" "3") #("2" "2" "3")) #(#("2" "2" "3") #("2" "2" "3")))
how can I change only one element in the vector?
===following code===
#lang racket
(define v (make-vector 2
                       (make-vector 2
                                    (vector "1" "2" "3"))))

(vector-set! (vector-ref (vector-ref v 0) 0) 0  "2")
v
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