Social Engineering at Work

I’ve never had social engineering done at me, but recently there was this guy who phone me by directly calling MX Telecom’s number. He said he was calling from DHL and that he had a package to be delivered for me. He wanted the name of two other people who would sign the delivery report in case I was not there. I complied and later a colleague told me that this is most likely a recruiter collecting names from the companies.