是的，我找到了解决方案.问题是未启用下载管理器.

Yes I found solution. The problem is didn't enabled download manager.

Go to the Settings > App
In the options click 'Show System Apps'
Find 'Download Manager' and open it
Click 'Notifications' under App Settings
Switch on Allow Notifications

参考:

https://***.com/a/43841708/1921263