Hiring manager permissions for clients
Read this article to learn more about hiring manager permissions at the organization level.
If your client would like to each of their hiring managers to be isolated from other hiring managers, you can enable a client-setting so that hiring managers can only access their own jobs and candidates.
Go to Clients -> Clients and find the client you want to update. Click "edit" to open their settings and look towards the bottom for "Job restriction settings."
After expanding this you can turn this on for this client like so: