Fortigate has 2 uplink How to track with both wan IP

Fortinet Firewall has 2 uplink (Internet) . I have installed Librenms on cloud. I added snmp using one ISP1 Wan IP. But when ISP1 is down in librenms it is showing down. But Fortinet Firewall is up via ISP2. I tried to add as new devoce with ISP2 WAN IP but it show following error
Cannot add Y.Y.Y.Y , already have device X.X.X.X with this IP Y.Y.Y.Y

ISP 1 WAN IP: X.X.X.X
ISP2 WAP IP:Y.Y.Y.Y

How to track my fortinet firewall with both wan IP.

either create two different hosts entries with fw-isp1 & fw-isp2 & allow duplicate sysnames or try using the “force add” option

Also, if polling on the public IP, be sure to use SNMPv3

Thaks for Reply. If I do like above for same device I have to add 2 node. I want one node tracked by 2 IP.

Not possible. Why not monitor by one IP and alert on port status? Not quite perfect, but will indicate if one or more ports is down.