Replace IP by DNS Name

Hello,

#########################      API Function Script      #########################
#------------------------------------------------------------------------------------------------------------
# Prerequisites:
#
# Requires -Version 3
#------------------------------------------------------------------------------------------------------------
# Initialize Variables
<# account info #>
$accessId = '8eNu95BddC4T2UkWgKcn'
$accessKey = 'blahblahblah'
$company = 'uclahealth'
#------------------------------------------------------------------------------------------------------------
# Functionize the reusable code that builds and executes the query
function Send-Request() {
    Param(
        [Parameter(position = 0, Mandatory = $true)]
        [string]$path,
        [Parameter(position = 1, Mandatory = $false)]
        [string]$httpVerb = 'GET',
        [Parameter(position = 2, Mandatory = $false)]
        [string]$queryParams,
        [Parameter(position = 3, Mandatory = $false)]
        [PSObject]$data
    )
    # Use TLS 1.2
    [Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12
    <# Construct URL #>
#    $url = "https://$company.logicmonitor.com/santaba/rest$path$queryParams"
    $url = "https://$company.logicmonitor.com/santaba/rest/device/devices/128"
    <# Get current time in milliseconds #>
    $epoch = [Math]::Round((New-TimeSpan -start (Get-Date -Date "1/1/1970") -end (Get-Date).ToUniversalTime()).TotalMilliseconds)
    <# Concatenate Request Details #>
    $requestVars = $httpVerb + $epoch + $data + $path
    <# Construct Signature #>
    $hmac = New-Object System.Security.Cryptography.HMACSHA256
    $hmac.Key = [Text.Encoding]::UTF8.GetBytes($accessKey)
    $signatureBytes = $hmac.ComputeHash([Text.Encoding]::UTF8.GetBytes($requestVars))
    $signatureHex = [System.BitConverter]::ToString($signatureBytes) -replace '-'
    $signature = [System.Convert]::ToBase64String([System.Text.Encoding]::UTF8.GetBytes($signatureHex.ToLower()))
    <# Construct Headers #>
    $auth = 'LMv2 ' + $accessId + ':' + $signature + ':' + $epoch
    $headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
    $headers.Add("Authorization", $auth)
    $headers.Add("Content-Type", 'application/json')
    $headers.Add("X-version", '2')
    <# Make request & retry if failed due to rate limiting #>
    $Stoploop = $false
    do {
        try {
            <# Make Request #>
            $response = Invoke-RestMethod -Uri $url -Method $httpVerb -Body $data -Header $headers
            $Stoploop = $true
        } catch {
            switch ($_) {
                { $_.Exception.Response.StatusCode.value__ -eq 429 } {
                    Write-Host "Request exceeded rate limit, retrying in 60 seconds..."
                    Start-Sleep -Seconds 60
                    $response = Invoke-RestMethod -Uri $url -Method $httpVerb -Body $data -Header $headers
                }
                { $_.Exception.Response.StatusCode.value__ } {
                    Write-Host "Request failed, not as a result of rate limiting"
                    # Dig into the exception to get the Response details.
                    # Note that value__ is not a typo.
                    Write-Host "StatusCode:" $_.Exception.Response.StatusCode.value__
                    Write-Host "StatusDescription:" $_.Exception.Response.StatusCode
                    $_.ErrorDetails.Message -match '{"errorMessage":"([\d\S\s]+)","errorCode":(\d+),'
                    Write-Host "LM ErrorMessage" $matches[1]
                    Write-Host "LM ErrorCode" $matches[2]
                    $response = $null
                    $Stoploop = $true
                }
                default {
                    Write-Host "An Unknown Exception occurred:"
                    Write-Host $_ | Format-List -Force
                $response = $null
                $Stoploop = $true
            }
        }
    }
} While ($Stoploop -eq $false)
Return $response
}
$httpVerb = 'GET'
$resourcePath = 'device/devices/128'
$queryParams = $null
$data = $null
$results = Send-Request $resourcePath $httpVerb $queryParams $data
foreach ($hostname in $results.items) {
    $sysname = (($hostname.systemProperties) | Where-Object -Property "name" -eq "system.sysname").value
    if ($sysname -match "\.") {
        $newName = $sysname.split(".")[0]
    } else {
        $newName = $sysname
    }
    if ($hostname.Name -eq $newName) {
        Write-Host "Name `"$($hostname.displayName)`" matched no change needed"
    } else {
    #Request Info
        $httpVerb = 'PATCH'
        $resourcePath = '/device/devices/128'
#       $queryParams = "?patchFields=Name&opType=replace"
        $queryParams = '?patchFields=displayName'
#       $data = @{
#           Name = $newName
#       } | ConvertTo-Json
        $data = '{"displayName":"newName"}'
        Send-Request $resourcePath $httpVerb $queryParams $data
        Write-Host "Changed host id $($hostname.id) Name from `"$($hostname.ips)`" to `"$newName`"."
    }
}

is giving an error:

Request failed, not as a result of rate limiting
StatusCode: 401
StatusDescription: Unauthorized
LM ErrorMessage HTTP 401 Unauthorized
LM ErrorCode 1400
 

Thanks,

Dom