Thank you for your email. We’re including the solution here as well in case it’s useful to other community members.
The Cause of the Problem
It appears that both sensors had a channel automatically downgraded by our systems, but the widgets didn’t properly reflect this. I’ve sent this to our development team so the issue can be resolved when they next work on the widget.
The Solution
We have manually downgraded the high-reading channel. This causes the widgets to display data from the other channel and should make them usable again. These manual downgrades will remain until removed by PurpleAir staff, so let us know if the readings improve after performing sensor maintenance or replacing the laser counters.