A recurring issue in redirect planning for content changes is easy to describe: only desktop URLs were tested after a migration. Resolving it requires checking the underlying condition as well as the visible result.
Find the likely cause
Device or routing differences were overlooked.
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
Test representative devices and URL patterns, including query parameters.
A redirect plan should preserve the visitor's intended task when a URL moves or a useful equivalent replaces it.
Check that the repair worked
Verify that real entry paths reach the intended content.
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: a migration loses images and downloadable resources. Map important assets and update references alongside page URLs.
Monitor the useful outcome
Track broken destinations, redirect chains, and successful access to important migrated content.
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.
Official reference for the platform or standard discussed: Google Search Central: site moves.