React page request successful but data not refreshing: common pitfalls for beginners

Problem Phenomenon New developers often encounter this situation: the API clearly returns new data, and you can see 200 OK in the Network tab, but the page still shows old content. After refreshing the browser, the data is normal again. I have been doing software development in the U.S. for over a decade, and I have seen these types of issues in backend systems, e-commerce management consoles…