There are a couple of places you can find when you lost WAN connectivity.
Security & SD-Wan > Appliance Status > Summary shows green/red indicator for connectivity or outage.
Or Security & SD-Wan > Appliance Status > Uplink will show missing areas if WAN1 or WAN2 are down.
In the example above the cellular uplink was repositioned twice and you can see WAN2 outage for brief periods (latency).
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