Updating a host record via powershell

[#1]

I am trying to update a host record IPv4 address with script.

The script returns error.  Invoke-RestMethod : Unable to connect to the remote server.

$Body = @{
    "@type" = "login"
    "username" = "crailey@xx.org"
    "password" = "pass!"
} | ConvertTo-Json
$header = @{
 "Accept"="application/json"
 "connectapitoken"="97fe6ab5b1a640909551e36a071ce9ed"
 "Content-Type"="application/json"
}

Invoke-RestMethod -Uri "10.10.0.2" -Method 'Post' -Body $body -Headers $header | ConvertTo-HTML

Invoke-Command -Computername 'ns3.mlgw.org' -scriptblock {
    $oldobj = get-dnsserverresourcerecord -name "10.5.6.56" -zonename "ad.xx.org" -rrtype "A"
    $newobj = get-dnsserverresourcerecord  -name "10.1.2.156" -zonename "ad.xx.org" -rrtype "A"
    $updateip = "10.1.2.0"
    $newobj.recorddata.ipv4address=[System.Net.IPAddress]:arse($updateip)
Set-dnsserverresourcerecord -newinputobject $newobj -oldinputobject $oldobj -zonename "ad.mlgw.org" - passthru
   
}

Does my code look correct to update host x ip with a new ip.  

[#2]

The address is stored in the host address record, not in the host record.  You will first need to locate the host address record, and update the address there.

Also the URI should be a REST endpoint, not just an IP address.  for example 'https://10.10.0.2/wapi/v2.4/request'