Claim to be from Windows Service Centre and my computer is gonna be blocked blah blah blah

Received a phone call (from (03) 9440 5232) and was told my computer is hacked and it needs urgent repair. He claimed he was calling from Microsoft. He told me to write down a very long serial number and then told me to say it back. Then he told me to go to the computer to access the number so that they can fix the hacking asap. He asked what is the leftmost lower key and I replied it is control key, then he asked what is the key next to it and I replied function key. I started to become suspicious and asked which computer he is talking about and he told me it is a laptop, which I don't use. Then I asked when I started to use this computer (as I had recently purchased it), he just hung up the phone. According to my internet research, other people have received calls from this phone number ((03) 9440 5232) which claimed to be Microsoft or Windows. The caller had Indian-sounding accent and there was background noise of lots of caller.

claimed that my windows OS had been hacked. Used the Assoc command to demonstrate their skill to gain trust by giving me the 888DCA60 number. Common CLSID number for millions of computers.

claiming to be from "Windows"

Claiming to be from Microsoft