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Could not authenticate to SharePoint Online using OAuth 2.0

 $username = "test@am.onmicrosoft.com"

$password = "******"

$cred = New-Object -TypeName System.Management.Automation.PSCredential -argumentlist $userName, $(convertto-securestring $Password -asplaintext -force)

Connect-SPOService -Url https://finders-admin.sharepoint.com -Credential $cred