@kumaravelu ,For our issue, could you firstly help to confirm if we can access SSRS Web service URL and Web portal URL successfully using Data reader account?
Meanwhile, please also check if there's any network or bad proxy in our environment.
To check the proxy entry from MonitoringHost.Exe.Config. we can go to location: C:\Program Files\Microsoft System Center\Operations Manager\Server and check if there's any
<defaultProxy>
<proxy proxyaddress=http://127.0.0.1:8888 **="true" />
<bypasslist>
</bypasslist>
</defaultProxy>
</system.net>
Please check the above information and if there's any update, feel free to let us know.
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