C++ 2d Array Class Function Call Help

I hope this question takes a simple fix, and I am just missing something very small.

I am in my second semester of C++ in college, and we are just getting into OOP. This is my first OOP program, and it is causing me a little problem. Here are the errors I am getting:

Member function must be called or its address taken in function displayGrid(int,Cell ( *)[20])
Member function must be called or its address taken in function Turn(int,int,Cell ( *)[20])
Member function must be called or its address taken in function Turn(int,int,Cell ( *)[20])
Warning: Parameter 'grid' is never used in function displayGrid(int,Cell ( *)[20])

Here is all of my code. I am aware It is much more code than necessary, sorry if it makes it more difficult. I was worried that I might accidentally delete something.

const int MAX=20;

//Struct Cell holds player and their symbol.
class Cell
{
 private:
  int Player;
  char Symbol;

 public:
  Cell(void);
  void setPlayer(int);
  void setSymbol(char);
  int getPlayer(void);
  char getSymbol(void);

};
 Cell::Cell(void)
 {
  Symbol ='-';
 }

 void Cell::setPlayer(int player_num)
 {
  Player = player_num;
 }

 void Cell::setSymbol(char rps)
 {
  Symbol = rps;
 }

 int Cell::getPlayer(void)
 {
  return Player;
 }

 char Cell::getSymbol(void)
 {
  return Symbol;
 }

  void Turn(int, int, Cell[MAX][MAX]);
  void displayGrid(int, Cell[MAX][MAX]);

void main(void)
{
 int size;

 cout << "How big would you like the grid to be: ";
 cin >> size;

    //Checks to see valid grid size
 while(size>MAX || size<3)
 {
  cout << "Grid size must between 20 and 3." << endl;
  cout << "Please re-enter the grid size: ";
  cin >> size;
 }

 int cnt=1;
 int full;
 Cell grid[MAX][MAX];

 //I use full to detect when the game is over by squaring size.
 full = size*size;
 cout << "Starting a new game." << endl;

 //Exits loop when cnt reaches full.
 while(cnt<full+1)
 {
  displayGrid(size, grid); //calls function to display grid

  if(cnt%2==0)  //if cnt is even then it's 2nd players turn
   cout << "Player 2's turn." << endl;
  else
   cout << "Player 1's turn" << endl;

  Turn(size, cnt, grid); //calls Turn do each players turn

  cnt++;
 }

 cout << endl;

 cout << "Board is full... Game Over" << endl;
 }


void displayGrid(int size, Cell grid[MAX][MAX])
 {
  cout << endl;
  cout << "  ";

  for(int x=1; x<size+1; x++)     // prints first row
   cout << setw(3) << x;       // of numbers.

  cout << endl;

  //Nested-For prints the grid.
  for(int i=1; i<size+1; i++)
  {
   cout << setw(2) << i;

    for(int c=1; c<size+1; c++)
    {
     cout <<  setw(3) << grid[i][c].getSymbol;
    }
    cout << endl;
   }

   cout << endl;
  }

void Turn(int size, int cnt, Cell grid[MAX][MAX])
  {
   char temp;
   char choice;
   int row=0;
   int column=0;

   cout << "Enter the Row: ";
   cin >> row;

   cout << "Enter the Column: ";
   cin >> column;

   //puts what is in the current cell in "temp"
   temp = grid[row][column].getSymbol;

   //Checks to see if temp is occupied or not
   while(temp!='-')
   {
    cout << "Cell space is Occupied..." << endl;
    cout << "Enter the Row: ";
    cin >> row;

    cout << "Enter the Column: ";
    cin >> column;

          temp = grid[row][column].getSymbol; //exits loop when finally correct
     }

   if(cnt%2==0) //if cnt is even then its player 2's turn
   {
    cout << "Enter your Symbol R, P, or S (Capitals): ";
    cin >> choice;
    grid[row][column].setPlayer(1);

   in >> choice;
       }

    //officially sets choice to grid cell
       grid[row][column].setSymbol(choice);
   }

   else //if cnt is odd then its player 1's turn
   {
    cout << "Enter your Symbol r, p, or s (Lower-Case): ";
    cin >> choice;
    grid[row][column].setPlayer(2);

    //checks for valid input by user1
    while(choice!= 'r' && choice!='p' && choice!='s')
    {
     cout << "Invalid Symbol... Please Re-Enter: ";
     cin >> choice;
       }

    //officially sets choice to grid cell.
       grid[row][column].setSymbol(choice);
   }

   cout << endl;
  }

Thanks alot for your help!