Constant calling to mislead u

Is anyone here aware of these people, one of them made a call first & asked for some person as I denied & confirmed that it's a wrong no., after few mins he made a call again and said that some other person 'Sonu' gave ur no., I denied, he asked 'aap btao aapka kya address hai, kyaa naam hai', I immediately hang up the call, the person named Sonu constantly called, I never answered, then he sent a whatsapp text 'Ok' This seems to me a fraud