Whilst it relates to another frequent flier programme, this website article gives some of the potential reasons, and steps you could take to save a FFP account. As you mention percysmith , the unknown part here is those other passengers, and this could have been the red flag that the OP would never know: https://www.headforpoints.com/2025/0...ccount-closed/

Ultimately if you're in the right alanyhq hopefully this will be resolved satisfactorily. Cathay is unlikely to ever say exactly why they banned your account, and we can speculate but wouldn't really know, but there isn't an obvious "red flag", so you just need to engage with them politely and support their process. The account has only been suspended rather than cancelled after all.