Thank you for counting my change until I understood it

On a Monday morning in a little shop in Garza I could not work out the colones and handed over a note that was far too large. The woman counted my change back into my hand three times, slowly, coin by coin, until I understood every one. She was not irritated. She said, again? I said, again. I now understand colones, and I understand her. I buy one mango from her every day so that I can keep practising. She has stopped counting. I have not.