A minor optimisation could be to set j = i + 1, as to avoid some repeated comparisons, otherwise it looks good

There are already open issues about incomplete tests, there's no point in raising new ones.

In c my solution was accepted, even if i checked only for blocks correctness,

{{1,2,3,1,2,3,1,2,3},
{4,5,6,4,5,6,4,5,6},
{7,8,9,7,8,9,7,8,9},
{1,2,3,1,2,3,1,2,3},
{4,5,6,4,5,6,4,5,6},
{7,8,9,7,8,9,7,8,9},
{1,2,3,1,2,3,1,2,3},
{4,5,6,4,5,6,4,5,6},
{7,8,9,7,8,9,7,8,9}}

should return false but my code returns true, in spite of this I passed all the tests.
please add check for row/column number repetition

grazie maestro <3

puoi evitare il break in quanto se si avvera quella condizione la funzione ritorna false, e quindi interrompe già il suo flusso uscendo dal ciclo. per il resto è ok <3