Device Down Due to no ICMP response false alarm

Hi guys , im watching this alarm (not real alarm) triggered very often.
Even on servers located at same subnet segment.
This is my validate.php output:

[[email protected]_wiber librenms]# su - librenms
Last login: Tue Oct 13 11:31:08 -03 2020 on pts/0
-bash-4.2$ php validate.php
Component | Version
--------- | -------
LibreNMS  | 1.68-41-ge7f2de7
DB Schema | 2020_09_24_000500_create_cache_locks_table (176)
PHP       | 7.3.20
Python    | 3.6.8
MySQL     | 5.5.65-MariaDB
RRDTool   | 1.4.8
SNMP      | NET-SNMP 5.7.2

[OK]    Composer Version: 1.10.15
[OK]    Dependencies up-to-date.
[OK]    Database connection successful
[OK]    Database schema correct

it seems no problems there.
This is server load and memory usage:

Server memory is almost near 100% … Can be the cause of those alarms ?
Is there something I can do to avoid those false alarms ?
Any thought would be wellcome.