Assuming you are the one who has administrator permission could you please try to use "Permission Helper" from "Jira Admin Helper" to dig into that further?
As per it's description: "The Permission Helper can help you figure out why a user can or can't see a certain issue."
You can learn more about it here:
https://support.atlassian.com/jira-cloud-administration/docs/use-the-jira-admin-helper/
It mentions "view other portals" are they customers or agents?
I was wondering if a security level was maybe set but you mention they see the issues in the list?
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.
have you inspected the project for the users that are seeing this? Do they have access? Is this NG or Classic? If they exist in the project then the next thing to look at is the permissions. Maybe a role or group was deleted and that role or group is used in the permission scheme.
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.
You must be a registered user to add a comment. If you've already registered, sign in. Otherwise, register and sign in.