Error scraping target

Hello Team

I’m having a problem where snmp_exporter would time out ( after 3 retries) while trying to collect metrics from a target which is a Cisco Router running snmp.
nearly 60 devices are configurated, all are working fine except 5 routers. please find the below log

INFO[0120] Error scraping target 172.X.X.X: Error walking target 172.X.X.X: Request timeout (after 3 retries) source=“collector.go:126”