public async Task <ActionResult <RegistrationAPI> > Create(RegistrationAPI user)
        {
            _context.RegistrationAPIUsers.Add(user);
            await _context.SaveChangesAsync();

            return(CreatedAtAction(nameof(GetById), new { id = user.ID }, user));
        }
        public async Task <IActionResult> Update(long id, RegistrationAPI user)
        {
            if (id != user.ID)
            {
                return(BadRequest());
            }

            _context.Entry(user).State = EntityState.Modified;
            await _context.SaveChangesAsync();

            return(NoContent());
        }