What happened with this attempted CC scam/fraud?

That’s also the case in Quebec and Ontario, the only provinces I have bought gas in.

I can’t do that . I can either

  1. pay with credit card and pump my own gas. Can’t enter any maximum. If I want to just put $20 worth in, I have to watch and stop when the meter gets to $20

  2. pay with either a credit card or cash at a full service pump. I have no idea what they do when I say $20 but I’m sure it’s the same procedure whether it’s cash or credit
    or

  3. pay with cash inside and they will authorize the pump for the amount I paid.

Ah, thanks.