Please help me with the task: InputValidation.Battleship

Hello, I’m working on this task:

Write a program that validates a battleship move. It first reads a letter [A–J] or [a–j] and then an integer [1–10], each from the new line. If the input for the move is valid, program should output “Next move is {letter}{number}.” Otherwise, it should output “Letter should be from A to J. Number from 1 to 10. Try again!” The program should continue to ask for and read values for the battleship move until the user inputs valid values for both of them. Pay attention: it should be case insensitive; ‘A’ and ‘a’ are both allowable. Your program should, however, output letter in the same case as it was entered. For example:
>a
>
Letter should be from A to J. Number from 1 to 10. Try again!

>10
>a
Letter should be from A to J. Number from 1 to 10. Try again!

>#
>10
Letter should be from A to J. Number from 1 to 10. Try again!

>c
>5
Next move is c5.

Here is my code:


namespace InputValidation
{
   class Battleship
   {
       static void Main(string[] args)
       {
           var letterAsString = Console.ReadLine();
           var numberAsString = Console.ReadLine();

           char letter;
           int number;
           bool valid = char.TryParse(letterAsString, out letter) && int.TryParse(numberAsString, out number);

           if((!char.TryParse(letterAsString, out letter)) || (!int.TryParse(numberAsString, out number)) || (char.ToLower(letter) > 'j') || (char.ToLower(letter) < 'a'))
           {
               valid = true;
           }
           else if((number < 1) || (number > 10))
           {
               valid = true;
           }
           while(!valid)
           {
               Console.WriteLine("Letter should be from A to J. Number from 1 to 10. Try again!");
               letterAsString = Console.ReadLine();
               numberAsString = Console.ReadLine();
           }

           Console.WriteLine($"Next move is {letter}{number}.");
       }
   }
}

Can anyone please help me to solve it?