Assume that John is taking interview of harry. In past, harry was an administrator but now he is not . what should harry say here?
JOHN : Harry, Tell me about your past experience
Harry : I was an administrator for two years at COMPANY A
Harry : I have been an administrator for two years at COMPANY A
I think they are just like "I did that for two years" and "i have done that for two years" But both refer to Past. But "I have done that for two years" sounds More accurate when we want to describe any time period (for,since). So i am thinking 2nd one is more accurate here.