.Net Blazor id The MERGE statement conflicted with the FOREIGN KEY constraint problem

I am working on a project and there is a trainer I follow.When I came to the update process, I started to get an error, when I went with Breakpoints, I realized that the QuizId value came 0000 in the save phase. When I check the database, all my connections are correct, id values are also available, but I have a problem with the output.

Questions.cs

[Key]public Guid Id { get; set; }public string Text { get; set; }public Guid QuizId { get; set; }[ForeignKey(nameof(QuizId))]public virtual Quiz Quiz { get; set; }public virtual ICollection<Options> Options { get; set; } = [];

Options.cs

[Key]public int Id { get; set; }public string Text { get; set; }public bool IsCorrect { get; set; }public Guid QuestionId { get; set; }[ForeignKey(nameof(QuestionId))]public virtual Questions Questions { get; set; }

Quiz.cs

  [Key]  public Guid Id { get; set; }  public string? Name { get; set; }  public int TotalQuestions { get; set; }  public int TimeInMinutes { get; set; }  public bool IsActive { get; set; }  public Guid CategoryId { get; set; }  [ForeignKey(nameof(CategoryId))]  public virtual Category? Category { get; set; }  public ICollection<Questions> Questions { get; set; } = [];

below is the block of code I used to save the data

public async Task<QuizApiResponse> SaveQuizAsync(QuizSaveDto dto){    var questions = dto.Question.Select(q => new Questions    {        Id = Guid.NewGuid(),        Text = q.Text,        Options = q.Option.Select(o => new Options        {            Id = 0,            Text = o.Text,            IsCorrect = o.IsCorrect        }).ToArray()    }).ToArray();    if (dto.Id == Guid.Empty)    {        var quiz = new Quiz        {            Id = Guid.NewGuid(),            Name = dto.Name,            CategoryId = dto.CategoryId,            TotalQuestions = dto.TotalQuestions,            TimeInMinutes = dto.TimeInMinutes,            IsActive = dto.IsActive,            Questions = questions        };        _context.Quizzes.Add(quiz);    }    else    {        var dbQuiz = await _context.Quizzes.FirstOrDefaultAsync(q => q.Id == dto.Id);//QuizId have        if (dbQuiz == null)        {            return QuizApiResponse.Fail("Quiz doesn't exists");        }        dbQuiz.CategoryId = dto.CategoryId;        dbQuiz.IsActive = dto.IsActive;        dbQuiz.Name = dto.Name;        dbQuiz.TimeInMinutes = dto.TimeInMinutes;        dbQuiz.TotalQuestions = dto.TotalQuestions;        dbQuiz.Questions = questions;//QuizId is 0000        _context.Quizzes.Update(dbQuiz);// burada QuizId null    }    try    {        await _context.SaveChangesAsync();        return QuizApiResponse.Success();    }    catch (Exception ex)    {        return QuizApiResponse.Fail(ex.Message);    }}

here is a visual of my database schema

the point I detected when I proceeded with breakpoint

the error I get is as follows

Microsoft.EntityFrameworkCore.Update[10000]An exception occurred in the database while saving changes for context type 'BlazingQuiz.Api.Data.Repositories.QuizContext'.Microsoft.EntityFrameworkCore.DbUpdateException: An error occurred while saving the entity changes. See the inner exception for details.---> Microsoft.Data.SqlClient.SqlException (0x80131904): The MERGE statement conflicted with the FOREIGN KEY constraint "FK_Options_Questions_QuestionId". The conflict occurred in database "BlazingQuiz", table "dbo.Questions", column 'Id'.at Microsoft.Data.SqlClient.SqlConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction) at Microsoft.Data.SqlClient.SqlInternalConnection.OnError(SqlException exception, Boolean breakConnection, Action1 wrapCloseInAction)at Microsoft.Data.SqlClient.TdsParser.ThrowExceptionAndWarning(TdsParserStateObject stateObj, Boolean callerHasConnectionLock, Boolean asyncClose)