Tic Tac Toe en C

Hello,
I created a C program for the tic-tac-toe game. But when I run it, it always says that the square has already been filled. Does anyone see what I did wrong?
Thank you very much in advance for your answers

Here is my program:
#include <stdio.h>
#define nblignes 3
#define nbcolonnes 3

char grid[nblignes][nbcolonnes];

/*Initialization of the tic-tac-toe grid to empty: */
void initializeGrid(char grid[nblignes][nbcolonnes])
{
int i, j ;
for (i=0 ; i<nblignes ; i++)
{
for (j=0 ; j<nbcolonnes ; j++)
{
grid[i][j] = ' ' ;
}
}
}

/*Displaying the tic-tac-toe grid: */
void displayGrid(char grid[nblignes][nbcolonnes])
{
int i, j ;
for (i=0 ; i<nblignes ; i++)
{
for (j=0 ; j<(nbcolonnes) ; j++)
{
printf("%c", grid[i][j]) ;
printf("|") ;
}
printf("\n") ;
printf("- - -\n") ;
}
return ;
}

/*Input for the coordinates of the symbol to put on the grid. If the coordinates
are out of the grid or if the square has already been filled, input is
refused, an error message is displayed and the player must play again. */
void placeSymbol(char symbol, char grid[nblignes][nbcolonnes])
{
int row, column ;
printf("Please provide the row and column numbers:") ;
do
{
scanf_s("%i %i", &row, &column) ;
if ((row>0) && (row<=nblignes) && (column>0) && (column<=nbcolonnes))
{
row-- ; /*to be compatible with array indices*/
column-- ;
if (grid[row][column]!=' ')
printf("The square has already been filled. Please choose another one:") ;
else { grid[row][column]=symbol ;
if (symbol=='X') {symbol='O' ; }
else {symbol='X' ; }
}
}
else printf("Row or column index incorrect. Please re-enter:") ;
} while(grid[row][column]!=' ') ;
}

/*Test to see if one of the players has won: */
int winningTest(char grid[nblignes][nbcolonnes], char symbol)
{
int i, j, sum, won ;
sum = 0 ;
won = 0 ;
for (i=0 ; i<nblignes ; i++)
{
for (j=0 ; j<nbcolonnes ; j++)
{
sum+=grid[i][j] ;
}
if((sum==237) || (sum==264))
{ won = 1 ; }
}
for(j=0 ; j<nbcolonnes ; j++)
{
for(i=0 ; i<nblignes ; i++)
{
sum+=grid[i][j] ;
}
if((sum==237) || (sum==264))
{ won = 1 ; }
}
if(grid[0][0] + grid[1][1] + grid[2][2] == 237 || grid[0][0] + grid[1][1] + grid[2][2] == 264)
{ won = 1 ; }
if(grid[0][2] + grid[1][1] + grid[2][0] == 237 || grid[0][2] + grid[1][1] + grid[2][0] == 264)
{ won = 1 ; }
if (won==1)
{ printf("Congratulations to the player with the ") ;
if(symbol=='X')
printf("X") ;
else
printf("O") ;
printf("who has won.\n") ;
}
/* Test if the grid is full:*/
if(won==0){
for(i=0 ; i<nblignes ; i++)
{
for(j=0 ; j<= nbcolonnes ; j++)
{
if(grid[i][j] != ' ')
won=2 ;
printf("Neither player has won") ;
}
}
}
return won ;
}

void main()
{
char grid[nblignes][nbcolonnes] ;
char symbol ;
int won ;
initializeGrid(grid) ;
displayGrid(grid) ;
printf("Please choose your symbol, O or X:") ;
scanf("%c", &symbol) ;
do
{ placeSymbol(symbol, grid) ;
displayGrid(grid);
winningTest(grid, symbol) ;
}
while(won=0) ;

}