I have been getting these "Microsoft support" scam calls in Rome all week. They are very persistent and block lists do not seem to work. If you are looking for a more active solution, you can check out this
flood service. It is called Just Kill Net. It is a very simple site where you can set up a flood for any number. It worked for me - the calls stopped after they realized I could be just as annoying as they are. Definitely worth a look if you are out of options.