I used to do this with abusive customers at the hotel I worked at, but I’d transfer them to a non existent extension.

It would ring for a while, then transfer back to me where I’d say, “looks like they didn’t answer, let me try again.”

Rinse and repeat until they fucked off.

I called Verizon FiOS support

Spent 45 minutes waiting while their AI claimed it was fixing the problem.

Called the same number again, said “agent” and got connected to a human being. The human being told me I called the wrong number and that he would try to transfer me to the correct number, but it wasn’t reliable (phone company can’t get phones working), so he told me the number I should have called.

It was the number I called.

I called back again, but this time I managed to get someone helpful who transferred me to someone who understood my problem well enough to tell me there’s nothing they can do and I’m fucked.