Judge-submission can't be checked by other students, just add your code with your question or use a pastebin. Here's a code that gives 100%, I think the tricky part was to include the final validation when the salary hits below or equal to 0 and to print out the final sinalry when larger than 0.

Best,

Code:

using System;

namespace salary
{
    class Program
    {
        static void Main(string[] args)
        {
            int tabs = int.Parse(Console.ReadLine());
            int salary = int.Parse(Console.ReadLine());
            for (int i = 1; i <= tabs; i++)
            {
                string penaltySites = Console.ReadLine();
                if (penaltySites == "Facebook")
                {
                    salary -= 150;
                }
                else if (penaltySites == "Instagram")
                {
                    salary -= 100;
                }
                else if (penaltySites == "Reddit")
                {
                    salary -= 50;
                }
                if (salary <= 0)
                {
                    Console.WriteLine("You have lost your salary.");
                    break;
                }
            }
            if (salary > 0)
            {
                Console.WriteLine($"{salary}");
            }
        }
    }
}