c#
using API.Entities;
using Microsoft.EntityFrameworkCore;
using System.Security.Cryptography;
using System.Text;
using System.Text.Json;

namespace API.Data
{
    public class Seed
    {
        public static async Task SeedUsers(DataContext context)
        {
            if (await context.Users.AnyAsync()) return;

            var userData = await File.ReadAllTextAsync("Data/UserSeedData.json");

            var options = new JsonSerializerOptions { PropertyNameCaseInsensitive = true };

            var users = JsonSerializer.Deserialize<List<User>>(userData, options);

            if(users == null) return;

            foreach (var user in users) {
                using var hmac = new HMACSHA512();

                user.UserName = user.UserName.ToLower();
                user.PasswordHash = hmac.ComputeHash(Encoding.UTF8.GetBytes("Pa$$w0rd"));
                user.PasswordSalt = hmac.Key;

                context.Users.Add(user);
                
            }
            await context.SaveChangesAsync();
        }
    }
}

c#
using API.Entities;
using Microsoft.EntityFrameworkCore;
using System.Security.Cryptography;
using System.Text;
using System.Text.Json;

namespace API.Data
{
    public class Seed
    {
        public static async Task SeedUsers(DataContext context)
        {
            if (await context.Users.AnyAsync()) return;

            var userData = await File.ReadAllTextAsync("Data/UserSeedData.json");

            var options = new JsonSerializerOptions { PropertyNameCaseInsensitive = true };

            var users = JsonSerializer.Deserialize<List<User>>(userData, options);

            if(users == null) return;

            foreach (var user in users) {
                using var hmac = new HMACSHA512();

                user.UserName = user.UserName.ToLower();
                user.PasswordHash = hmac.ComputeHash(Encoding.UTF8.GetBytes("Pa$$w0rd"));
                user.PasswordSalt = hmac.Key;

                context.Users.Add(user);
                
            }
            await context.SaveChangesAsync();
        }
    }
}

fail: Program[0]
      An error occurred during migration
      System.Text.Json.JsonException: JSON deserialization for type 'API.Entities.User' was missing required properties, including the following: PasswordHash, PasswordSalt
         at System.Text.Json.ThrowHelper.ThrowJsonException_JsonRequiredPropertyMissing(JsonTypeInfo parent, BitArray requiredPropertiesSet)
         at System.Text.Json.Serialization.Converters.ObjectDefaultConverter`1.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
         at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value, Boolean& isPopulatedValue)
         at System.Text.Json.Serialization.JsonCollectionConverter`2.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, TCollection& value)
         at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value, Boolean& isPopulatedValue)
         at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, JsonSerializerOptions options, ReadStack& state)
         at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan`1 utf8Json, JsonTypeInfo`1 jsonTypeInfo, Nullable`1 actualByteCount)
         at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan`1 json, JsonTypeInfo`1 jsonTypeInfo)
         at System.Text.Json.JsonSerializer.Deserialize[TValue](String json, JsonSerializerOptions options)
         at API.Data.Seed.SeedUsers(DataContext context) in C:\Users\pc\source\repos\DatingApp\API\Data\Seed.cs:line 19
         at Program.<Main>$(String[] args) in C:\Users\pc\source\repos\DatingApp\API\Program.cs:line 30

fail: Program[0]
      An error occurred during migration
      System.Text.Json.JsonException: JSON deserialization for type 'API.Entities.User' was missing required properties, including the following: PasswordHash, PasswordSalt
         at System.Text.Json.ThrowHelper.ThrowJsonException_JsonRequiredPropertyMissing(JsonTypeInfo parent, BitArray requiredPropertiesSet)
         at System.Text.Json.Serialization.Converters.ObjectDefaultConverter`1.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value)
         at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value, Boolean& isPopulatedValue)
         at System.Text.Json.Serialization.JsonCollectionConverter`2.OnTryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, TCollection& value)
         at System.Text.Json.Serialization.JsonConverter`1.TryRead(Utf8JsonReader& reader, Type typeToConvert, JsonSerializerOptions options, ReadStack& state, T& value, Boolean& isPopulatedValue)
         at System.Text.Json.Serialization.JsonConverter`1.ReadCore(Utf8JsonReader& reader, JsonSerializerOptions options, ReadStack& state)
         at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan`1 utf8Json, JsonTypeInfo`1 jsonTypeInfo, Nullable`1 actualByteCount)
         at System.Text.Json.JsonSerializer.ReadFromSpan[TValue](ReadOnlySpan`1 json, JsonTypeInfo`1 jsonTypeInfo)
         at System.Text.Json.JsonSerializer.Deserialize[TValue](String json, JsonSerializerOptions options)
         at API.Data.Seed.SeedUsers(DataContext context) in C:\Users\pc\source\repos\DatingApp\API\Data\Seed.cs:line 19
         at Program.<Main>$(String[] args) in C:\Users\pc\source\repos\DatingApp\API\Program.cs:line 30

c#
using API.Extensions;

namespace API.Entities
{
    public class User
    {
        public int Id{ get; set; }

        public required string UserName{ get; set; }
        public required byte[] PasswordHash { get; set; } = [];
        public required byte[] PasswordSalt { get; set; } = [];

        public DateOnly DateOfBirth { get; set; }
        public required string KnownAs{ get; set; }
        public DateTime Created { get; set; } = DateTime.UtcNow;
        public DateTime LastActive { get; set; } = DateTime.UtcNow;

        public required string Gender { get; set; }
        public string? Introduction { get; set; }
        public string? Interests { get; set; }
        public string? LookingFor { get; set; }

        public required string City {  get; set; }
        public required string Country { get; set; }
        public List<Photo> Photos { get; set; }

        public int GetAge()
        {
            return DateOfBirth.CalculateAge();
        }
    }
}

c#
using API.Extensions;

namespace API.Entities
{
    public class User
    {
        public int Id{ get; set; }

        public required string UserName{ get; set; }
        public required byte[] PasswordHash { get; set; } = [];
        public required byte[] PasswordSalt { get; set; } = [];

        public DateOnly DateOfBirth { get; set; }
        public required string KnownAs{ get; set; }
        public DateTime Created { get; set; } = DateTime.UtcNow;
        public DateTime LastActive { get; set; } = DateTime.UtcNow;

        public required string Gender { get; set; }
        public string? Introduction { get; set; }
        public string? Interests { get; set; }
        public string? LookingFor { get; set; }

        public required string City {  get; set; }
        public required string Country { get; set; }
        public List<Photo> Photos { get; set; }

        public int GetAge()
        {
            return DateOfBirth.CalculateAge();
        }
    }
}