SharePoint Online: Delete Unique Permissions in a Subsite using PowerShell

#Load SharePoint CSOM Assemblies
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.dll"
Add-Type -Path "C:\Program Files\Common Files\Microsoft Shared\Web Server Extensions\16\ISAPI\Microsoft.SharePoint.Client.Runtime.dll"

#To call a non-generic Load Method
Function Invoke-LoadMethod() {
    Param(
            [Microsoft.SharePoint.Client.ClientObject]$Object = $(throw "Please provide a Client Object"),
            [string]$PropertyName
        )
   $Ctx = $Object.Context
   $Load = [Microsoft.SharePoint.Client.ClientContext].GetMethod("Load") 
   $Type = $Object.GetType()
   $ClientLoad = $Load.MakeGenericMethod($Type)
 
   $Parameter = [System.Linq.Expressions.Expression]::Parameter(($Type), $Type.Name)
   $Expression = [System.Linq.Expressions.Expression]::Lambda([System.Linq.Expressions.Expression]::Convert([System.Linq.Expressions.Expression]::PropertyOrField($Parameter,$PropertyName),[System.Object] ), $($Parameter))
   $ExpressionArray = [System.Array]::CreateInstance($Expression.GetType(), 1)
   $ExpressionArray.SetValue($Expression, 0)
   $ClientLoad.Invoke($Ctx,@($Object,$ExpressionArray))
}

#Config Parameters
$SiteURL= "https://crescent.sharepoint.com/sites/marketing/2018"

#Get Credentials to connect
$Cred = Get-Credential

Try {
    #Setup the context
    $Ctx = New-Object Microsoft.SharePoint.Client.ClientContext($SiteURL)
    $Ctx.Credentials = New-Object Microsoft.SharePoint.Client.SharePointOnlineCredentials($Cred.UserName,$Cred.Password)
    
    #Get the Web
    $Web = $Ctx.Web
    $Ctx.Load($Web)
    $Ctx.ExecuteQuery()

    #Check if the given subsite is using unique permissions
    Invoke-LoadMethod -Object $Web -PropertyName "HasUniqueRoleAssignments"
    $Ctx.ExecuteQuery()

    #Reset broken inheritance
    If($Web.HasUniqueRoleAssignments)
    {
        #delete unique permissions of a subsite in sharepoint online powershell
        $Web.ResetRoleInheritance()
        $Web.Update()
        $Ctx.ExecuteQuery()    
        Write-host -f Green "Unique Permissions Removed from the Site!"
    }
    Else
    {
        Write-host -f Yellow "Site is Already Inheriting Permissions from the Parent!"
    }
}
Catch {
    write-host -f Red "Error:" $_.Exception.Message
}

#Config Variables
$SiteURL = "https://crescent.sharepoint.com/sites/marketing/2018"
 
#Connect PnP Online
Connect-PnPOnline -Url $SiteURL -Credentials (Get-Credential)
 
#Get the web
$Web = Get-PnPWeb

#Remove unique permissions
$Web.ResetRoleInheritance()
Invoke-PnPQuery