After having a router reboot over the weekend, some graphs are no longer displaying data and new graphs have been created.

From the first screenshot, some graphs like processors are populating correctly, while others like traffic are empty.  This router has been in observium for years.  The only thing that changed was a reboot over the weekend due to a power issue.  No upgrades, changes, etc.

In some cases, the "old" graph for an interface is showing nothing, but a new graph for that interface seems to have been automatically created and is now showing data (second screenshot).

Is there any way to fix this?  I could probably delete the device completely and re-add it, but I hate to loose all of the historical data from it.

thanks