> ## Documentation Index
> Fetch the complete documentation index at: https://help.maestra.io/llms.txt
> Use this file to discover all available pages before exploring further.

# How to Read Customer Change History After a Merge

When two customer profiles merge in Maestra, their change histories merge too. That means the **Change history** tab on the resulting customer profile shows events from both original customers, woven together in chronological order. Knowing how to read that combined timeline is the fastest way to understand what happened before, during, and after a merge.

## What the Change history tab tracks

The **Change history** tab records every modification made to a customer profile, including:

* Personal data
* Contact information (email, phone)
* Identifiers
* Custom fields
* Customer merge events (deduplication)
* Contact removals in favor of the priority profile

## How histories combine on merge

When two profiles are merged, their histories are joined into a single chronological stream. Every change made to either customer — before they were merged and after — appears on the resulting profile's **Change history** tab in the order it occurred.

This lets you see the full sequence of actions across both original customers, even the ones that happened while they still existed as separate records.

## Example

Say two customers with MaestraIDs `1337` and `1338` were merged because they shared the same email address. The combined history might look like this:

| Time     | MaestraID | Event                                                         |
| -------- | --------- | ------------------------------------------------------------- |
| 18:05:14 | 1337      | First customer registered                                     |
| 18:09:06 | 1337      | Profile data edited                                           |
| 18:09:52 | 1338      | Second customer registered; deduplication triggered the merge |

Each row shows when the event happened, which MaestraID it belonged to at the time, and what changed.

## Reading the timeline

When you review the **Change history** tab, pay attention to two things:

* **Timestamps** — they tell you the exact order of events across both original customers.
* **MaestraIDs** — if different IDs appear in the timeline, those entries happened while the customers still existed as separate profiles. Once the merge event appears, every later entry belongs to the surviving profile.

<Tip>
  If you see two different MaestraIDs in the same history, that's your signal that the events come from two profiles that were later merged. Use the merge event itself as the dividing line between "before" and "after."
</Tip>