Ask them how you can help them not to make the same mistake again. Not knowing the specific situation makes it hard to offer specific advice, but in software there are specific tools (e.g. IDEs, linters, CIs, tests, etc.) that help people avoid known mistakes. Sometimes having better docs or specific checklist (e.g. "your bug must have these fields filled in before we can work on it") helps.
If that doesn't help, ask the manager the same - emphasizing you are not attacking the person but looking for a way to stop wasting time on correcting the same repeating mistake which adds to costs and decreases productivity. That may generate some resentment (so trying to resolve it directly first is prudent) but if you avoid framing it as a personal fault it would usually help.
If that doesn't help, ask the manager the same - emphasizing you are not attacking the person but looking for a way to stop wasting time on correcting the same repeating mistake which adds to costs and decreases productivity. That may generate some resentment (so trying to resolve it directly first is prudent) but if you avoid framing it as a personal fault it would usually help.