20.7.6 New Traffic Controller Issues

[asrare]

Since i update to 20.7.6 and 20.7.7 i have issues when i view more than 30 min the graph, all traffic is freezing.
The graph also can't save my selected and pined last wan interface (1 lan, 2 wan) and color graph are quiet the same as the first wan.
I have a KMV Proxmox_6.3.3 VM
Here is the message box shown :

Error at /usr/local/opnsense/mvc/app/controllers/OPNsense/Diagnostics/Api/TrafficController.php:74 - Invalid argument supplied for foreach() (errno=2)

Tell me how to send more logs if needed.

[Wombat]

I have also ben seeing error since upgrade 2 days ago to 2.7.6.
"/usr/local/opnsense/mvc/app/controllers/OPNsense/Diagnostics/Api/TrafficController.php:74 - Invalid argument supplied for foreach() (errno=2)"
Reported it using the OPNSense Crash reporting