I remember a cashier in Turkey. My Turkish was way too rudimentary, and she didn’t seem to speak other languages. So, when I did not understand something she said, she repeated the exact same thing, only louder. I still had no idea what she was saying; I had paid, there was absolutely no problem, my wallet was in my hand, not fallen on the floor… And she repeated the thing she said before, even louder, looking like she was expecting something from me. I looked puzzled, and tried to communicate using other languages, gestures, trying to guess, playing mime. Understanding I was clueless about what she had said, she, of course, repeated that same thing… almost yelling, then grabbed my hand, took some coins, gave me a banknote, and then (thankfully) ignored me. Oh, so she needed change. Pointing to the coins would have worked like a charm.
Moral of the story: shouting the same thing ever so loud won’t make you understood; adjusting your message does the trick.