Horror braking Mondeo – brake heavy and weak

Hello together. Had a scare customer this morning : I drive with approx. 60 km/h on the Aachen outer ring. Suddenly my friend calls “cautious care !!!” There I see already 2 huge milling edges on the road. About 3 cm deep… I step on the brake fully, but I needed a lot more strength than usual. I stepped on it as hard as I could, but I couldn’t stop in time. So we thundered at about 25 km/h over the edge. thanks to God nothing has gone aputt. There was nothing to feel about brake assistant. Okay, the mass inertia of the Mondeo is great, but that it slows so badly when it comes to it, I wouldn’t have thought. Have you ever had similar experiences?