I've had the same calls, As had my wife. When you speak to an agent, They ask you what number they called you on.... I have worked with auto-dialers and these systems show you the number you have called, And can be integrated with database systems to pull up the relevant information instantly... But when I tell them, "you called me", They hang up. This is a scam fishing expedition. Block the number.
The agent tell me that they are calling me from Collexa or something like that. I cant find them in country in the internet. They ask me to identify myself and when i dont they hang up, But later call again days later. I check my credit score via Equifax and have nothing on my record. I blocked them hoping to avoid future calls.
Very fishy and dont know what are the mechanisms to verify if it is a legitimate call or not.