I've been experiencing the exact same issue for about a week or moe
It comes along with other major problems on the AF website. For instance, I'm totally unable to modify any flight directly online since November 2024. I can see the fares, select the options for the new flight, but when I'm supposed to process to the actual exchange, wether it is free or it comes with a fee, I'm requested to call them. It's getting very bothersome and the Gold service does not seem to care.