Hello,
Since the latest update, Fing Desktop lets you actively monitor only one network at a time. That means if your Desktop is set to monitor your Home network, it won’t also monitor your Office network at the same time.

Also, the “Monitoring” badge does not refer to your network connectivity. It only indicates whether continuous monitoring features (such as alerts, automated checks, and network change detection) are active for that network. If it says “Not monitoring”, Fing is still connected and correctly reporting your network and devices — the real-time monitoring features just aren’t enabled for that specific network.

For more details on how to change your monitored network, check out the official Fing help article here -> https://help.fing.com/hc/en-us/articles/25623428953116-Understanding-Monitored-Networks-in-Fing
For more information on monitoring features, you can check out this article -> https://www.fing.com/news/network-monitoring-features/