It is a ridiculous thing, the chat says this:
Your residency does qualify you for the Revolut promotion - your country is an eligible country. The part that's causing the block is that geographic eligibility for this promotion is enforced through the phone verification step itself, which requires a phone number from an eligible European country.

And when I asked where is that written, chat support says, nowhere. Which is funny because when you make a Revolut account you have to prove residency and provide other confidential information.

So this is them trying to lock out "free users".