Issue with Automation Accounts>Runbooks: The remote server returned an error: (401) Unauthorized - azure

Question

I am facing on an issue with azure script. I created a runbook in automation accounts and I gave to new app the contributor rights on subscription, but when I run the code I see:
The remote server returned an error: (401) Unauthorized. Invoke-WebRequest : The remote server returned an error: (401) Unauthorized. At line:82 char:13 + $All_BSOD = Invoke-WebRequest -Uri $Top50_BSOD_URL -Method GET -Heade ... + ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~ + CategoryInfo : InvalidOperation: (System.Net.HttpWebRequest:HttpWebRequest) [Invoke-WebRequest], WebException + FullyQualifiedErrorId : WebCmdletWebResponseException,Microsoft.PowerShell.Commands.InvokeWebRequestCommand .
At below there are the code:
# Function to send Teams notif
Function Send_Notif
{
param(
$Text,
$Title
)
$Body = #{
'text'= $Text
'Title'= $Title
'themeColor'= "$Color"
}
$Params = #{
Headers = #{'accept'='application/json'}
Body = $Body | ConvertTo-Json
Method = 'Post'
URI = $Webhook_URL
}
Invoke-RestMethod #Params
}
#*****************************************************************
# Part to fill
#*****************************************************************
# Teams webhoot link
$Webhook_URL = "personal link"
# Choose the top x devices (default is 50)
$Top_count = 50
# Teams notif design
$Notif_Title = "Top 50 devices with BSOD"
$Notif_Message = "Here is the list of top 50 devices with BSOD on the last 30 days"
$Color = "2874A6"
#*****************************************************************
# Getting a token
$url = $env:IDENTITY_ENDPOINT
$headers = New-Object "System.Collections.Generic.Dictionary[[String],[String]]"
$headers.Add("X-IDENTITY-HEADER", $env:IDENTITY_HEADER)
$headers.Add("Metadata", "True")
$body = #{resource='https://graph.microsoft.com/' }
$script:accessToken = (Invoke-RestMethod $url -Method 'POST' -Headers $headers -ContentType 'application/x-www-form-urlencoded' -Body $body ).access_token
# Authentication
Connect-AzAccount -Identity
$headers = #{'Authorization'="Bearer " + $accessToken}
# Graph URL to use
$Top50_BSOD_URL = "https://graph.microsoft.com/beta/deviceManagement/userExperienceAnalyticsDevicePerformance?dtFilter=all&`$orderBy=blueScreenCount%20desc&`$top=$Top_count&`$filter=blueScreenCount%20ge%201%20and%20blueScreenCount%20le%2050"
$StartupHistory_url = "https://graph.microsoft.com/beta/deviceManagement/userExperienceAnalyticsDeviceStartupHistory?" + '$filter=deviceId%20eq%20%27' + "$DeviceID%27"
# Getting BSOD info
$All_BSOD = Invoke-WebRequest -Uri $Top50_BSOD_URL -Method GET -Headers $Headers -UseBasicParsing
$All_BSOD_JsonResponse = ($All_BSOD.Content | ConvertFrom-Json)
$Get_All_BSOD = $All_BSOD_JsonResponse.value
$BSOD_Array = #()
ForEach($BSOD in $Get_All_BSOD)
{
$Device_Model = $BSOD.model
$Device_Name = $BSOD.deviceName
$BSOD_Count = $BSOD.blueScreenCount
$DeviceID = $BSOD.id
$Get_StartupHistory = Invoke-WebRequest -Uri $StartupHistory_url -Method GET -Headers $Headers -UseBasicParsing
$Get_BSOD_JsonResponse = ($Get_StartupHistory.Content | ConvertFrom-Json)
$Get_BSOD = ($Get_BSOD_JsonResponse.value | Where {$_.restartCategory -eq "blueScreen"})[-1]
$Last_BSOD_Date = [datetime]($Get_BSOD.startTime)
$Last_BSOD_Code = $Get_BSOD.restartStopCode
$OS = $Get_BSOD.operatingSystemVersion
$BSOD_Obj = New-Object PSObject
Add-Member -InputObject $BSOD_Obj -MemberType NoteProperty -Name "Device" -Value $Device_Name
Add-Member -InputObject $BSOD_Obj -MemberType NoteProperty -Name "Model" -Value $Device_Model
Add-Member -InputObject $BSOD_Obj -MemberType NoteProperty -Name "Count" -Value $BSOD_Count
Add-Member -InputObject $BSOD_Obj -MemberType NoteProperty -Name "OS version" -Value $OS
Add-Member -InputObject $BSOD_Obj -MemberType NoteProperty -Name "Last BSOD" -Value $Last_BSOD_Date
Add-Member -InputObject $BSOD_Obj -MemberType NoteProperty -Name "Last code" -Value $Last_BSOD_Code
$BSOD_Array += $BSOD_Obj
}
$BSOD_Table = $BSOD_Array | ConvertTo-HTML -Fragment
$BSOD_Table = $BSOD_Table.Replace("<table>","<table border='1'>")
$Text_Message = "$Notif_Message<br><br>
$BSOD_Table
"
Send_Notif -Text $Text_Message -Title $Notif_Title | out-null
Anybody can help me?
thank you
PS: this is the original webpage text
My aim is to get a notification to all bsod\devices in my enviroment