Last several years when I did get through I was always offered a second knife. I don't believe I purchased a second. I recall about 4 years ago they had knives available for about 3 days after the sale day. That could have been the year the phone lines were down on that particular day.
Michael was manning the phones back then. Never in a hurry and always had as much time as you needed.
So, was the museum open? Hope you had a chance to visit.