Hello. Neiffson,
In addition to enabling and configuring the SNMP service, it is necessary to release traffic in the firewall entry rules for the ports used (usually UDP/161 and UDP/162).
You can check if packages are reaching the firewall through the command:
tcpdump -i any port 161 -nn
If there is no traffic, also validate if the source device is pointing correctly to the IP of the firewall and if there is no intermediate lock on the route.
