Everyone has done this at one time or another. I think the best thing to do is to simply say “I’m so sorry, I am terrible with names, what is it again?” To avoid it in the future, I heard someone say once that when you are first introduced, say the person’s name when speaking to them a few times.. IE: Nice to meet you….insert name here… Then whenever you speak to that person say there name, and it should help you to remember it longer.