Invoke-TppRestMethod not working in VenafiSession class.

[wilddev65]

Operating System: Windows 10
VenafiPS version: 4.1.2
PowerShell version: 5.1

# Steps to reproduce

Write-Verbose "Get APIKey and connect to TPP Server."
New-VenafiSession -Server $TPPServer -Credential $TPPCredential

# Expected behavior

A new API key is obtained by lines 138-143 of VenafiSession.ps1:
        $response = Invoke-TppRestMethod @params
        $this.Key = [pscustomobject] @{
            ApiKey     = $response.ApiKey
            Credential = $Credential
            Expires    = $response.ValidUntil
        }


# Actual behavior

Error:
WARNING: Key-based authentication will be deprecated in release 21.4 in favor of token-based.  Get started with token authentication today, https://docs.venafi.com/Docs/current/TopNav/Content/SDK/AuthSDK/t-SDKa-Setup-OAuth.php.
Invoke-TppRestMethod : The term 'Invoke-TppRestMethod' is not recognized as the name of a cmdlet, function, script file, or operable program. Check the spelling of the name, or if a path was included, verify that the path is correct and try again.
At C:\Program Files\WindowsPowerShell\Modules\VenafiPS\4.1.2\Classes\VenafiSession.ps1:138 char:21
+         $response = Invoke-TppRestMethod @params
+                     ~~~~~~~~~~~~~~~~~~~~
    + CategoryInfo          : ObjectNotFound: (Invoke-TppRestMethod:String) [], CommandNotFoundException
    + FullyQualifiedErrorId : CommandNotFoundException

NOTE: Changing line 138 to 'Invoke-VenafiSession' fixes the issue.

[gdbarron]

Nice find. This is an issue on v5 and not v7.