If the backlog never reflects new evidence, start by preserving one representative example. It gives the investigation a concrete reference and makes the eventual correction easier to judge.
Find the likely cause
Priorities are fixed despite changed conditions.
Treat this as an explanation to verify against the actual work. Look at the input, the relevant decision, and the final result together. If the evidence does not support this diagnosis, investigate the mismatch before applying a convenient but unrelated fix.
Make the targeted correction
Review the list when important customer or performance evidence changes.
A useful backlog makes trade-offs visible so the team spends effort on work with a credible connection to customer and business needs.
Check that the repair worked
Update the reasoning as well as the order.
Repeat the check on the final version that the reader or customer will encounter. An approved draft, a preview, and a published result can differ; the acceptance decision should concern the version people actually use.
Prevent the next related failure
A separate issue to watch for is this: the backlog contains solutions without defined problems. Write the user or business problem before evaluating the proposed fix.
Monitor the useful outcome
Track completed useful work, aging blocked items, and the reasons priorities change.
Keep a short record of the original symptom, the evidence behind the diagnosis, and the result of the acceptance check. That record makes the solution reusable when the same condition appears again, without assuming that every superficially similar problem has the same cause.