WKHTTPCookieStore getAllCookies只能运行一次并停止

Question

如何多次调用httpCookieStore.getAllCookies，因为它似乎只能在模拟器上运行，而不是在实际设备上运行。

    private var httpCookieStore: WKHTTPCookieStore  {
        return WKWebsiteDataStore.default().httpCookieStore
    }


    if #available(iOS 11.0, *) {
        httpCookieStore.getAllCookies { (cookies) in
            for cookie in cookies {
                if let domain = domain {
                    if cookie.domain.contains(domain) {
                        cookieDict[cookie.name] = cookie.properties as AnyObject?
                    }
                } else {
                    cookieDict[cookie.name] = cookie.properties as AnyObject?
                }
            }
            completion(cookieDict)
        }
    } else {
        // Fallback on earlier versions
    }

由于某种原因，httpCookieStore仅被调用一次，而每隔一次在设备上不起作用，但在模拟器上则很好。