Problem with Greek words?

Hello to all!

I recently moved all my files to a new PC. At the same time I bought Scrivener again (I had the first version, so I upgraded to Version: 3.1.1.0 (1463331) 64-bit). I write in Greek and the problem is that now, on this new edition of Scrivener, on the new PC, all the Greek suggestions on Spelling come not as words, but as question marks (???). Why is that? Do I have to download something extra?

Please advice

Thanks!