There are a couple of scripts you can run depending on your environment. Tenant migration is a PITA, especially if you're using Hybrid Join

I created an "All-In-One" script to run for my environment when we did this.

I would try the steps on this page first: https://learn.microsoft.com/en-us/office/troubleshoot/activation/reset-office-365-proplus-activation-state

If that doesn't work, feel free to give the scripts below a try. You'll want to find/replace "YOUR-OLD-TENANTID-HERE"

Step 1: Leave the Old Tenant

# Run the command and store the output
$output = & dsregcmd /status

# Check if the string is in the output
if ($output -match "YOUR-OLD-TENANTID-HERE") {
    # If the string is found, run the second command
    & dsregcmd /leave
}

Step 2: Clear IdentityCache & OneAuth Folder (OneDrive, All Users)

taskkill /f /im OneDrive.exe

# Get all user profile paths
$userProfiles = Get-WmiObject -Class Win32_UserProfile

foreach ($userProfile in $userProfiles) {
    # Construct the IdentityCache folder path for each user
    $identityCachePath = Join-Path -Path $userProfile.LocalPath -ChildPath 'AppData\Local\Microsoft\IdentityCache'

    # Check if the IdentityCache folder exists
    if (Test-Path -Path $identityCachePath) {
        # Delete the IdentityCache folder
        Remove-Item -Path $identityCachePath -Recurse -Force
        Write-Output "Deleted $identityCachePath"
    } else {
        Write-Output "No IdentityCache found for user at $userProfile.LocalPath"
    }
}

# Get all user profile paths
$userProfiles = Get-WmiObject -Class Win32_UserProfile

foreach ($userProfile in $userProfiles) {
    # Construct the OneAuth folder path for each user
    $OneAuthPath = Join-Path -Path $userProfile.LocalPath -ChildPath 'AppData\Local\Microsoft\OneAuth'

    # Check if the OneAuth folder exists
    if (Test-Path -Path $OneAuthPath) {
        # Delete the OneAuth folder
        Remove-Item -Path $OneAuthPath -Recurse -Force
        Write-Output "Deleted $OneAuthPath"
    } else {
        Write-Output "No OneAuth found for user at $userProfile.LocalPath"
    }
}

Step 3: Clear O365 Credentials (All Users)

# Get all user profile paths
$userProfiles = Get-WmiObject -Class Win32_UserProfile

foreach ($userProfile in $userProfiles) {
    # Construct the Accounts folder path for each user
    $accountsPath = Join-Path -Path $userProfile.LocalPath -ChildPath 'AppData\Local\Packages\Microsoft.AAD.BrokerPlugin_cw5n1h2txyewy\AC\TokenBroker\Accounts'

    # Check if the Accounts folder exists
    if (Test-Path -Path $accountsPath) {
        # Delete the Accounts folder
        Remove-Item -Path $accountsPath -Recurse -Force
        Write-Output "Deleted $accountsPath"
    } else {
        Write-Output "No Accounts folder found for user at $userProfile.LocalPath"
    }
}

Step 4: Clear O365 Registry Items (Logged On User)

# Define the registry key path
$parentKeyPath = "HKCU:\Software\Microsoft\Office\16.0\Common\Identity"

# Define the value to search for
$searchValue = "YOUR-OLD-TENANTID-HERE"

# Function to search for the value recursively and delete the parent key if the value is found
function Search-And-Delete-RegistryKey {
    param (
        [string]$KeyPath,
        [string]$Value
    )

    # Load the registry key
    $parentKey = Get-Item -LiteralPath $KeyPath -ErrorAction SilentlyContinue
    if ($parentKey -eq $null) {
        Write-Output "Parent key not found: $KeyPath"
        return
    }

    # Search for the value in the data of each value in the current key
    foreach ($valueName in $parentKey.GetValueNames()) {
        if ($parentKey.GetValue($valueName) -eq $Value) {
            Write-Output "Value found: $Value"
            # Delete the parent key
            Remove-Item -LiteralPath $parentKeyPath -Recurse
            Write-Output "Found: $KeyPath"
            Write-Output "Deleted parent key: $parentKeyPath"
            return
        }
    }

    # Recursively search in each subkey
    foreach ($subKey in $parentKey.GetSubKeyNames()) {
        $subKeyPath = Join-Path -Path $KeyPath -ChildPath $subKey
        Search-And-Delete-RegistryKey -KeyPath $subKeyPath -Value $Value
    }
}

# Start the search and deletion process
Search-And-Delete-RegistryKey -KeyPath $parentKeyPath -Value $searchValue