Hotel AC Hotels by Marriott di Paris

Had 2 rooms booked under my name. My family was on a different flight than I was. We took a delay due to weather so arrived later than planned. I messaged the hotel via the app to see if they could allow my sister to check in. They said it wasn't possible. I advised my sister. They decided to drop their bags off and someone working the front desk checked them into one of my reservations, thankfully. I arrived a few hours later and check into the second reservation. We were on a 2 week family European trip. My expenses were on my business Bonvoy AMEX while her expenses were on my personal Bonvoy Amex. Therefore, I replaced the credit card on my second room with my personal AMEX. The agent who checked me in was truly the only pleasant agent I interacted with. She was extremely professional and kind. She even recommended The Heavenway restaurant, which was by far the best restaurant I dined at in Paris. You must try their mushroom risotto and caesar salad, truly spectacular. The front desk agent was kind enough to upgrade my partner and I to a more spacious suite, which I appreciated. She asked if I preferred welcome points or breakfast for my status. I originally opted for breakfast, but then realizing our departure time, changed it to points. The room was of good size. Water pressure was very decent for Europe. AC worked well and kept the room at a comfortable temperature. The hotel has recently gone under a renovation so everything felt clean and crisp. It was a pleasant surprise as their photos on the Marriott site did not reflect that at the time of booking, though they do now. The renovation was well executed. Surprisingly, even the towels felt new. The Issues occurred that evening when I attempted to use my mobile key to access my room and noticed my second room was no longer under my Bonvoy account. I messaged the property and they informed me the second reservation was now under my sister's name. I explained the reservation was under my name, I was simply trying to allow her to check-in prior to my arrival, to which they originally declined. They then replied she supplied her own credit card, to which I wasn't eligible for points, which is true under Marriott's terms and conditions. I then explained i supplied a new credit card at check-in, which replaced hers. They were unconvinced as the numbers didn't match. I explained I had 3 AMEX's and my charges were going under my business amex and hers were going under my personal. They asked me to come down and show both cards ending in the last numbers they had on file were under my name. I obliged. The two females I spoke to at the front desk were confused when I went downstairs. I explained what happened via the chat line on their app and they verified both credit cards were under my name. They advised me they were going to add the second reservation back to my Bonvoy account and change the name back to mine, which did occur. Once I was back in my room, everything they promised, transpired