I assume your issue is related to the "IBM Tivoli Netcool/OMNIbus SNMP Probe". If this assumption is correct, then open this IBM Knowledge Center link and navigate to the 'Troubleshooting' section/topic (which links-to/details information about issues and FAQs that might help you to resolve your issue)
https://www.ibm.com/support/knowledgecenter/en/SSSHTQ/omnibus/probes/snmp/wip/concept/snmp_introduction_c.html