_signInManager.GetExternalLoginInfoAsync（）始终使用身份用户Oauth返回null

Question

info始终为null，但如果使用facebook，它运行良好。我正在使用ASP.NET core 2.1 outh。我正在寻找不适合我的任何解决方案。所以我被卡住了 这是我的Startup.cs文件代码

public void ConfigureServices(IServiceCollection services)
    {
        services.Configure<CookiePolicyOptions>(options =>
        {
            // This lambda determines whether user consent for non-essential cookies is needed for a given request.
            options.CheckConsentNeeded = context => true;
            options.MinimumSameSitePolicy = SameSiteMode.None;
        });

        services.AddDbContext<ApplicationDbContext>(options =>
            options.UseSqlServer(
                Configuration.GetConnectionString("DefaultConnection")));
        services.AddIdentity < IdentityUser,IdentityRole > ()
             .AddDefaultUI()
             .AddEntityFrameworkStores<ApplicationDbContext>()
             .AddDefaultTokenProviders();

        services.AddMvc().SetCompatibilityVersion(CompatibilityVersion.Version_2_1);
        services.AddAuthentication().AddGoogle(options => {
            options.ClientId = "dghdhfhfh46335333-.apps.googleusercontent.com";
            options.ClientSecret = "Efhgjhk432fh";
            options.UserInformationEndpoint = "https://www.googleapis.com/oauth2/v1/certs";
        })

    }

这是ExternalLogin.cshtml中的方法

public async Task<IActionResult> OnGetCallbackAsync(string returnUrl = null, string remoteError = null)
    {
        returnUrl = returnUrl ?? Url.Content("~/");
        if (remoteError != null)
        {
            ErrorMessage = $"Error from external provider: {remoteError}";
            return RedirectToPage("./Login", new {ReturnUrl = returnUrl });
        }
       var info = await _signInManager.GetExternalLoginInfoAsync();
        if (info == null)
        {
            ErrorMessage = "Error loading external login information.";
            return RedirectToPage("./Login", new { ReturnUrl = returnUrl });
        }

        // Sign in the user with this external login provider if the user already has a login.
        var result = await _signInManager.ExternalLoginSignInAsync(info.LoginProvider, info.ProviderKey, isPersistent: false, bypassTwoFactor : true);
        if (result.Succeeded)
        {
            _logger.LogInformation("{Name} logged in with {LoginProvider} provider.", info.Principal.Identity.Name, info.LoginProvider);
            return LocalRedirect(returnUrl);
        }
        if (result.IsLockedOut)
        {
            return RedirectToPage("./Lockout");
        }
        else
        {
            // If the user does not have an account, then ask the user to create an account.
            ReturnUrl = returnUrl;
            LoginProvider = info.LoginProvider;
            if (info.Principal.HasClaim(c => c.Type == ClaimTypes.Email))
            {
                Input = new InputModel
                {
                    Email = info.Principal.FindFirstValue(ClaimTypes.Email)
                };
            }
            return Page();
        }
    }