Wouldn't even try to help
I bought a house 2 years ago that had a hikvision camera system install and was still linked to the previous owner, I tried to link it to my WiFi system but was unable to as it was still linked to the other man. I don't know who or where he is, so I contacted hikvision and explained the situation he said "sorry mate I can't help you" Can't or won't is the question!