为什么获取手机UI树报错

我设置了等待元素如果超时后就获取手机页面的UI树，为什么报错了

[错误] [2023-12-06 10:40:24.824] 【子流程1】中第【9】条指令出错: An unknown server-side error occurred while processing the command. Original error: Timed out after 15534ms waiting for the root AccessibilityNodeInfo in the active window. Make sure the active window is not constantly hogging the main UI thread (e.g. the application is being idle long enough), so the accessibility manager could do its work