omg, i used a global variable to check if the puzzle was solved but forgot to reset it for an new puzzle!

thank you very much!

I got a solution as

[[6, 1, 5, 7, 2, 4, 8, 3, 9],

[4, 8, 7, 3, 9, 5, 1, 6, 2],

[9, 2, 3, 1, 8, 6, 5, 7, 4],

[5, 9, 8, 4, 3, 2, 7, 1, 6],

[1, 3, 6, 8, 7, 9, 2, 4, 5],

[2, 7, 4, 6, 5, 1, 9, 8, 3],

[8, 4, 9, 5, 1, 3, 6, 2, 7],

[7, 6, 2, 9, 4, 8, 3, 5, 1],

[3, 5, 1, 2, 6, 7, 4, 9, 8]]

but it reminded me that "Value is not what was expected"

is there any problem with my solution? thx