Jan 27, 2022 - 05:32 AM
Here the voice does say: "vous devez réserver une table au restaurant". She speaks a bit fast, linking all words together, which might be why it's not easy for you to hear "au".
It's one of these cases where depending on people's accent or speed you might not always hear every single part of a phrase. Keep it up! It will get clearer and clearer as you move on..
Jan 27, 2022 - 12:40 PM