Hi @Hari Haran A
Follow the steps below:
1.Install Microsoft Teams PowerShell Module.
Install-Module -Name MicrosoftTeams -Force -AllowClobber
2.Import the Teams module and connect to Microsoft Teams using an admin user with an O365 license.
Import-Module MicrosoftTeams
$userCredential = Get-Credential
Connect-MicrosoftTeams -Credential $userCredential
3.Create an application access policy for your app.
New-CsApplicationAccessPolicy -Identity Test-policy -AppIds "{app id}" -Description "description here"
4.Grant the policy to the user.
Grant-CsApplicationAccessPolicy -PolicyName Test-policy -Identity "{user object id}"
Hope this helps.
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