Same here: two ring call to a private pre-paid phone. We get a bunch of these calls EACH & EVERY time we buy minutes for this phone from CALLINGMART.com; ALWAYS using PAYPAL. They are DESPERATE to get our credit card #; NOT gonna happen! We'd stop doing business with them but we save significantly over time. LOVE to see 'em get heavily FINED, though.
Simply came up on my phone as a missed call meaning that it disconnected as soon as it confirmed it was an existing number but before it could trigger my phone to signal an incoming call. Means it's some sort of robo call.