My client is stated the IP address is not one of theirs or is not related to their network

We scan the publicly facing DNS records for the provided domain. That means that all hosts detected by the Upfort Cyber Risk Report are related to the Insured's network, as the hosts need to be present on the Insured's DNS record to be present in the report.

If the Insured is using a hosting provider on a shared server, it's not uncommon for multiple, unrelated hosts on the same server to share the same IP address. 
If this is the case, searching for the webpage by pasting the IP address may return an unrelated host, which can lead users to believe that the IP detection is incorrect, but as above, we are detecting all hosts from the Insured's DNS record.

If in doubt, you can reach out to the Customer Support team to review the report results manually and confirm the host's validity.  You can find our contact details here: How do I reach out to Upfort?