I got this error when trying to seed data to the database

“The instance of entity type ‘Unit’ cannot be tracked because another instance with the same key value for {‘UnitId’} is already being tracked. When attaching existing entities, ensure that only one entity instance with a given key value is attach…”

This is the function call in program.cs:

using (var scope = app.Services.CreateScope())
{
    var dbContext = scope.ServiceProvider.GetRequiredService<DBContext>();
    dbContext.Database.EnsureCreated();
    SeedData.Seed(dbContext);
}

And here is the code to seed the data:

namespace cuahangbanle.DBData.Seed
{
    public static class SeedData
    {
        public static void Seed(DBContext dbContext)
        {
            if (!dbContext.Roles.Any())
            {
                dbContext.Roles.Add(new Role { RoleId = "Admin", RoleName = "Administrator" });
            }
            dbContext.SaveChanges();

            if (!dbContext.Accounts.Any())
            {
                dbContext.Accounts.Add(new Account
                {
                    AccountId = "ACC001",
                    Username = "admin",
                    Password = "admin",
                    RoleId = "Admin",
                });
            }
            dbContext.SaveChanges();

            if (!dbContext.Suppliers.Any())
            {
                dbContext.Suppliers.AddRange(
                    new Supplier { SupplierId = "SUP001", SupplierName = "Supplier 1", CreatedBy = "ACC001" },
                    new Supplier { SupplierId = "SUP002", SupplierName = "Supplier 2", CreatedBy = "ACC001" }
                );
            }
            dbContext.SaveChanges();

            if (!dbContext.Units.Any())
            {
                dbContext.Units.AddRange(
                    new Unit { UnitId = "can", SmallUnit = "can", LargeUnit = "box" },
                    new Unit { UnitId = "package", SmallUnit = "package", LargeUnit = "box" }
                );
            }
            dbContext.SaveChanges();

            if (!dbContext.Categories.Any())
            {
                dbContext.Categories.AddRange(
                    new Category { CategoryId = "CAT001", CategoryName = "Category 1", CreatedDate = DateTime.Now, CreatedBy = "ACC001" },
                    new Category { CategoryId = "CAT002", CategoryName = "Category 2", CreatedDate = DateTime.Now, CreatedBy = "ACC001" }
                );
            }
            dbContext.SaveChanges();

            if (!dbContext.Products.Any())
            {
                try
                {
                    dbContext.Products.AddRange(
                    new Product { ProductId = "PRD001", ProductName = "Coca", CategoryId = "CAT001", SupplierId = "SUP001", SupplierName = "Supplier 1", UnitId = "can", PurchasePrice = 7000, SalePrice = 8000, ProfitMargin = 14.29M, Profit = 1000, Stock = 10 },
                    new Product { ProductId = "PRD002", ProductName = "Hao Hao spicy noodles", CategoryId = "CAT002", SupplierId = "SUP002", SupplierName = "Supplier 2", UnitId = "package", PurchasePrice = 3000, SalePrice = 4000, ProfitMargin = 33.33M, Profit = 1000, Stock = 20 }
                );
                }
                catch(Exception ex)
                {
                    Console.WriteLine(ex.Message);
                }
            }
            dbContext.SaveChanges();
        }
    }
}

The error part goes here:

try
{
    dbContext.Products.AddRange(
      new Product { ProductId = "PRD001", ProductName = "Coca", CategoryId = "CAT001", SupplierId = "SUP001", SupplierName = "Supplier 1", UnitId = "can", PurchasePrice = 7000, SalePrice = 8000, ProfitMargin = 14.29M, Profit = 1000, Stock = 10 },
      new Product { ProductId = "PRD002", ProductName = "Hao Hao spicy noodles", CategoryId = "CAT002", SupplierId = "SUP002", SupplierName = "Supplier 2", UnitId = "package", PurchasePrice = 3000, SalePrice = 4000, ProfitMargin = 33.33M, Profit = 1000, Stock = 20 }
    );
}
catch(Exception ex)
{
    Console.WriteLine(ex.Message);
}

How should I fix this error?