Short answer

When a complaint time and logger curve do not line up, list handover, reported event and logger times separately. Check whether the logger clock was set correctly and preserve the raw file. The curve covers only its recorded interval. Reconcile the post-handover gap with customer or site records, and report findings separately from interpretation.

When a complaint arrives, open the related run record. A clean curve does not cover the product's full history; the complaint may concern an event after handover.

Build the timeline

List run, physical handover and reported event times side by side. Keep logger clock and download time separate; file creation time is not measurement time.

What the record can say

If the recorded interval stays within limits, it shows only the measured conditions for that interval.
If a rise appears before handover, review that section alongside the handover process.
If there is no measurement, do not call it normal temperature; mark the interval as missing data.

What the record cannot say

A logger shows temperature at its location and over its own recording interval, not the product itself. A run curve alone cannot explain post-handover conditions.

For a mismatch, first establish which time and question each source covers.

Read complaints together

Match complaints by product group, delivery point and period. One event does not show cause; recurring similarities help select the link to investigate.

The wording of a reply

Present the raw record separately from interpretation. If times differ, explain the time zone used and any uncertainty about the logger clock setting.

Keep the record reachable. Because complaints can arrive late, set retention according to product requirements and the customer agreement. Link the raw file, correction note and handover evidence in one case file.

When complaint time and the curve do not line up