Newsflash: Being sued by buyers

We put our home in the market September 2023, in Texas. Moved to Florida. We accepted an offer middle of March. Had the inspection, the buyer chose the inspector. Did all that we needed to do. They asked for us to have the AC cleaned and inspected. Had that done. Our realtor was there the whole time with the AC guy. He cleaned and serviced and fixed what needed to be done. Mind you the AC has always worked and was working at the time. Our realtor sent over the AC inspection and the buyers signed off on it and bought the home. Now they went to move in last weekend and they are saying the AC isn’t working. They said the AC report we gave them said the AC could use some kind of Freon or something but I didn’t get it at that time. The buyers have their Uncle attorney saying that we knew it needed Freon or something and that we had been having people come and put it in there to keep it running. We have never had an issue with the AC. We haven’t had anyone put anything in it. We’ve been gone for 6 months. We only had the AC cleaned and inspected because they asked for that.So question, since it said that it needed the Freon on the report and they signed off on it can they come back and sue us for that? Shouldn’t they have negotiated that before closing. I do not remember it saying anything or denying any work but our realtor said something about it on the report. Also their realtor asked them if they wanted us to pay for a year of home warranty, which would have eliminated this issue, They declined saying they wanted to get one in their own. We are thinking about getting an attorney and asking for attorney fees. We knew nothing of anything wrong with the AC. We didn’t hide anything from them. Can anyone give me their opinion on what they think about the situation? Our realtor thinks it’s all crazy and she is a 20 year realtor and doesn’t have one mark on her license.