Azure AD B2C移动端登录仅返回IdToken，无Access Token问题排查

我在移动端应用中登录自行搭建的Azure AD B2C门户，门户可正常启动，支持用户创建与登录操作。但登录完成后，从IDE中可见返回的数据仅包含IdToken（可解码查看用户名等信息），未获取到Access Token，不清楚原因。

已配置以下常量：

public static readonly string ClientId = "asd"; 
public static readonly string[] Scopes = { "openid", "offline_access" };
// The next code to add B2C
public static readonly string TenantName = "skillbasedauth";
public static readonly string TenantId = $"{TenantName}.onmicrosoft.com";
public static readonly string SignInPolicy = "B2C_1_Client";
public static readonly string AuthorityBase = $"https://{TenantName}.b2clogin.com/tfp/{TenantId}/";
public static readonly string AuthoritySignIn = $"{AuthorityBase}{SignInPolicy}";
public static readonly string IosKeychainSecurityGroups = "com.microsoft.adalcache";

同时已在后台设置了Scopes与返回URL，附上对应配置截图，请问是否存在遗漏的配置项？

内容的提问来源于stack exchange，提问作者inno