All parties have returned to Australia. The children have recently turned 17. Yes, I have contacted support enforcement as decribed: Sent the DA a letter with copies of my date stamp in passport, legal residency in Australia, Australian driving licence, copy of my lease for my house, electric bills. Have filled up and sent the correct notarised forms for termination, modification ( he does not want support). My son lives with me full time and I am financially responsible for him. That is the change of custody. My daughter lives with me half the time. The payee ( other parent has contacted the support enforcement with signed documents as stated. Thanks