Drop in accuracy after evaluating the model


I have trained my model and then applied QAT on it and re-train it again. During training the QAT model I can see that my metrics are doing very well. But, when I evaluate my model after the train phase has been finished, I see a drop in metrics.

I have 2 questions:

  1. As far as I understand, my QAT model is fine, but the problem is in evaluation, right?
  2. Why this drop after evaluating my model? Is this related to the evaluation dataset?
    NB: I am using the same train and test dataset.