Hi @Neeharika Gurijala,
Thank you for posting in this community.
The problem seems to be with the newly created search service application. Since we can't reproduce your situation, we need to narrow down the problem and try some things.
Please kindly provide more information below to let us work further:
**1.**Please refer this article to make sure you are following the correct steps for the search service application you created using PowerShell.
How To Configure Search Service Application Using PowerShell
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**2.**If the PowerShell is right, try creating a new Search Service program using the user GUI and see if the problem persists.
**3.**You can refer to this article to troubleshoot your 503 error: SharePoint Troubleshooting: The Remote server returned an error (503) server unavailable
**4.**Searchadmin.svc and serachservice.svc do not exist in IIS, most likely because your search service application was not configured successfully. Please try the above steps to redeploy the search service application and check again.
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