$groupmembers = Get-AzureADGroupMember -ObjectId $oldGroupId -All $true

foreach ($employeeId in $usersToAddExisting) {
        $user = Get-AzureADUser -Filter "extension_sfdsdfdfdd519_employeeNumber eq '$employeeId'"
        if($user -ne $null){
        if ($user.Count -eq 1) {
            $isUserMemberOfGroup = $groupmembers | Where-Object { $_.UserPrincipalName -like "$($user.UserPrincipalName)" }
            if ($isUserMemberOfGroup -eq $null) {
                Add-AzureADGroupMember -ObjectId $oldGroupId -RefObjectId $user.ObjectId
                #Remove-AzureADGroupMember -ObjectId $oldGroupId -MemberId $user.ObjectId
                Write-Output "Added user $($user.UserPrincipalName) to group xyz"
            } else {
                Write-Output "$($user.UserPrincipalName) already present in group $employeeId"
            }
        } else {
            Write-Output "User with Employee ID $employeeId not found."
        }
        }
        else{Write-Output "User with Employee ID $employeeId not found."}
    }