How did the scammers find out the phone number and that the purchase was made?

Question

ebay

At 13:51 I made a purchase on eBay with payment via PayPal with a Visa Classic card.
At 13:53 an SMS is received from the number [phone] with the content "Your bank card is blocked". And they ask you to call this number.
The question is, how did they know that I would just pay for the order? Where is the vulnerability? At the mobile operator, at the bank or somewhere else?
Mac OS X Yosemite computer, computer connected by cable to a DD-WRT router. Some kind of virus, of course, maybe, but very unlikely, because SMS is in Russian, and under Mac viruses are made mainly for the US.
The seller on eBay seems to be legitimate too - www.ebay.com/usr/drhotdeal
When buying a phone number in clear text, it does not shine anywhere. I did not enter it from the keyboard.

Answer 1

Certainly a coincidence. Normal wiring. Still popular are "mom, I'm in trouble - I need money ..."
Do not try to call - you can run into redirection with premium billing.

Answer 2

first of all, look for viruses on your computer, maybe the announcement was created by scammers

Answer 3

Call from a landline, listen to what they say) If they know the details of the transaction, then there is some kind of leak.
Might just be a coincidence

Answer 4

You didn't say the most important thing: is the card actually blocked or not?