The test procedures malfunction from time to time. I just had some data I generated a couple of years ago questioned. The submitter resubmitted material pulled at the same time and stored since then. One result was confirmed, another was not confirmed. So, when I tested two years ago, I showed twice that the results were the same, but now it doesn’t show up. Why? The vial the sample was stored in was contaminated? I don’t know. It happens.
K