Ibis Budget Muenchen City Olympiapark

I booked this hotel in March for a two night stay in May. I received an email from the hotel saying, "Ihre Zahlung wurde bestätigt. (payment confirmed)" So, all good. When I arrived, I was told that my reservation was "storniert" (cancelled). I asked why. The receptionist said she didn't know. Another receptionist told me that maybe my credit card was not accepted by Accor because they are in France. Accor is the parent company. I asked why my Deutsche Bank credit card, which I have used all over the world, would be rejected by a company because it was in France. She did not know. I was in town for a class and had to take another room, for which I was charged 71.10€ more than my booking price. I used the same credit card, and...it worked. Ok, this is obviously a scam being run by Accor or by the local hotel. I'm not sure which. I emailed Accor and they tell me that they cancelled it because I did not pay. But I have a confirmation that says I DID pay. So this is obviously a lie. And even if my card was rejected, why didn't the company send me an email informing me so that I could pay a different way? Whether they are incompetent or fraudulent, there is no excuse for their behaviour. I demanded a refund of the 71.10 extra charge and they refused. Well then my answer is that I will never again book a room at an Accor-owned hotel.