Leetcode question Valid Sudoko

I am solving this question using backtracking but I am getting WA for this test case.
[[".",“8”,“7”,“6”,“5”,“4”,“3”,“2”,“1”],[“2”,".",".",".",".",".",".",".","."],[“3”,".",".",".",".",".",".",".","."],[“4”,".",".",".",".",".",".",".","."],[“5”,".",".",".",".",".",".",".","."],[“6”,".",".",".",".",".",".",".","."],[“7”,".",".",".",".",".",".",".","."],[“8”,".",".",".",".",".",".",".","."],[“9”,".",".",".",".",".",".",".","."]]

My output is false but expected output is true.
Problem link: https://leetcode.com/problems/valid-sudoku/
My code: https://ide.codingblocks.com/s/143021