A powerbank never comes with a charger, not even for 180 francs, and in my opinion that's a pretty exaggerated price for such a powerbank. To charge it, you need a high-quality charger, e.g. one of these:

Aukey Omnia PA-B6S + USB C cable (90 W, GaN Technology, Power Delivery 3.0, Quick Charge 4.0, Adaptive Fast Charge)