Bulk assigning Office 365 licenses using PowerShell

I've completed this in the past successfully but I'm running into some issues this time.  Below is the PowerShell script I'm running:

Connect-MSOLService -Credential $adminCredential

$AccountSkuId = "msllbc:OFFICESUBSCRIPTION_STUDENT"

$UsageLocation = "US"

$LicenseOptions = New-MsolLicenseOptions -AccountSkuId $AccountSkuId

$Users = Import-Csv c:\Users.csv

$Users | ForEach-Object {

Set-MsolUser -UserPrincipalName $_.UserPrincipalName -UsageLocation $UsageLocation

Set-MsolUserLicense -UserPrincipalName $_.UserPrincipalName -AddLicenses $AccountSkuId -LicenseOptions $LicenseOptions

}

This is the error I'm receiving:

Set-MsolUserLicense : Unable to assign this license because it is invalid. Use
the Get-MsolAccountSku cmdlet to retrieve a list of valid licenses.
At C:\Add_License_New.ps1:14 char:20
+ Set-MsolUserLicense <<<<  -UserPrincipalName $_.UserPrincipalName -AddLicense
s $AccountSkuId -LicenseOptions $LicenseOptions
    + CategoryInfo          : OperationStopped: (:) [Set-MsolUserLicense], Mic
   rosoftOnlineException
    + FullyQualifiedErrorId : Microsoft.Online.Administration.Automation.Inval
   idUserLicenseException,Microsoft.Online.Administration.Automation.SetUserL
  icense

I have verified the license is valid.  Any ideas?  Thanks!