public async Task <IActionResult> SendChangeEmail([FromBody] SendChangeEmailRequest request)
        {
            if (!ModelState.IsValid)
            {
                return(BadRequest());
            }

            var user = await _userManager.FindByNameAsync(User.Identity.Name);

            if (user == null)
            {
                return(BadRequest());
            }

            var code = await _userManager.GenerateChangeEmailTokenAsync(user, request.NewEmailAddress);

            string baseURL = $"{Request.Scheme}://{Request.Host.Value}";
            await _emailSender.SendChangeEmail(user, request.NewEmailAddress, code, baseURL);

            return(Ok());
        }