When form errors erase what the visitor already entered, another broad rewrite or another batch of output may leave the underlying problem intact. Diagnose the relevant failure before changing the whole process.
Find the likely cause
Validation is implemented without preserving state.
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
Retain valid entries and explain how to correct the specific error.
A form should request the information needed for the next step while making expectations and recovery clear.
Check that the repair worked
Submit a controlled invalid value and test recovery.
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 submit button gives no feedback. Provide a clear processing state and confirmed outcome.
Monitor the useful outcome
Track successful submissions, field errors, inquiry quality, and device-specific completion issues.
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.