I am a newly appointed HR Executive. I have no experience and joined four days ago. My question is, some days ago, I conducted an interview for the position of a secretary. The candidate presented me with some experience letters, but I suspect they may be fake. Please advise me on how to verify her background. She has provided her previous employer's company address, and I have sent someone there. However, they informed him that they do not disclose employee details to third parties. Please assist me.