Private/Services/Disconnect-SfBOnline.ps1

function Disconnect-SfBOnline {

    [CmdletBinding()]
    param ()

    try {
        
        $SfBOSession = Get-SfBOnlineSession

        if ($null -ne $SfBOSession) {

            Remove-PSSession -Session ($SfBOSession) -ErrorAction Stop
            Remove-Module -Name 'SkypeOnlineConnector' -Force -ErrorAction Stop
            Write-Verbose -Message 'The Skype for Business Online PSSession is now closed.' -Verbose
        }
    }
    catch {

        Write-Warning -Message ('Unable to remove PSSession for Skype for Business Online - {0}' -f $_.Exception.Message)
        return
    }
}