I say 'new scam' but I am pretty sure it is anything but. I use Skype a fair bit, mainly for work but a bit socially. I get plenty of requests from people to become contacts. I block the vast majority. Sometimes they are just there waiting when I put Skype on after a few days.
Today, and not for the first time, I found myself included in a conference call of six people that was calling me up although Skype was actually off. The first name was French, then other names were Francophone, Anglophone and possibly Russian. So I blocked it en bloc. I know none of them. There was no message explaining what they wanted from me and even if there had been it would have needed to be very good indeed. Strangers often find out things they need not know and then use them to get into your contacts.
If you do not know people just block them and when the second box comes up register 'abuse' if you feel that way inclined. There is a very high chance somebody is out to scam you, just do not give them the chance.