Called and left no message. A Non-Fixed VOIP service not associated with an address and could be obtained by individuals that are outside the country. Common Non-Fixed VOIP providers include Google Voice and Skype. Fraudsters can take advantage of the ease of registration with Non-Fixed VOIP services to perform elaborate schemes and criminal activity that are untraceable. Identifying suspect phone numbers early that belong to Non-Fixed VOIP providers is an important first step in fraud prevention and protection.

I get a call from this number or another 339 number almost every day. They never leave  message and I don't know who they are

I get calls from these 339 numbers every single day and they call 2 - 3 times back to back, no message left either ... I don't know the number(s) and never answer. I block the number and then they call the next time with a one or two digit change of the last four digits. I'm getting real tired of these calls!!!!