Hi Gayathri,
You may need to raise a request to enable your user in Reltio Support Portal.
Few years ago, whoever has access to Reltio can login to Zendesk portal, but looks like now its changed and only named users in Zendesk can login irrespective of access you hold in Reltio.
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Gowthamprabhu Sivaraj
AstraZeneca
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