How to troubleshoot when React Query invalidateQueries doesn't work: Pitfalls I encountered on a backend list page

The Problem Recently, I was working on an order status drawer in a U.S. SaaS backend project. The API returned 200, the mutation entered onSuccess, and I even wrote queryClient.invalidateQueries, but the order list just wouldn't refresh. The most annoying part was that the data was correct after a manual page refresh, so QA immediately said, "Your frontend cache isn't being cleared properly."…