Is this a bug in poller for this particular device?

I’m receiving warnings about unpolled devices which have worked fine for longer time and i’m not sure why. It seems to solve itself after a while but one cant help wonder. Polling time is around 60s for these devices and warning comes randomly. It doesnt apply to all devices at the same time but some of them. from day to day.

I ran poller debug to capture what might be wrong and this came out:

Call to a member function firstWhere() on null {"exception":"[object] (Error(code: 0): Call to a member function firstWhere() on null at /home/librenms/LibreNMS/OS/Timos.php:643)"} 



In Timos.php line 643:
                                                  
  Call to a member function firstWhere() on null  
Version 1.68-50-g6cd42b3ee - Fri Oct 16 2020 15:07:29 GMT+0200
Database Schema 2020_10_03_1000_add_primary_key_transport_group_transport (186)
Web Server Apache/2.4.29 (Ubuntu)
PHP 7.2.24-0ubuntu0.18.04.7
Python 3.6.9
MySQL 10.1.44-MariaDB-0ubuntu0.18.04.1
Laravel 7.28.3
RRDtool 1.7.0