在iOS的getStream中进行以下操作似乎无效

Question

我正在使用以下代码。我没有收到任何回调。

     let loggedInUserFeedId = FeedId(feedSlug: "timeline", userId: Client.shared.currentUserId!)
    let loggedInUserFlatFeed = Client.shared.flatFeed(loggedInUserFeedId)
    let otherUserFeedId = FeedId(feedSlug: "timeline", userId: otherUserId)

    loggedInUserFlatFeed.follow(toTarget: otherUserFeedId, activityCopyLimit: 10) { (result) in
        print("Result of following:")
        print(try? result.get())
    }