> ## 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.

# Can You Block Customer Profile Merging

Yes. If you assign a unique identifier to each customer, you can prevent Maestra from merging customer profiles that have different IDs.

## How to block merging

In the settings for the customer's unique identifier, turn on the **Do not merge customers with different IDs** option.

<Steps>
  <Step title="Open the unique identifier settings">
    Go to the parameters of the unique customer identifier you use to distinguish customers in your system.
  </Step>

  <Step title="Enable the option">
    Activate **Do not merge customers with different IDs**.
  </Step>
</Steps>

Once enabled, Maestra will keep customer profiles separate whenever they carry different values of that identifier, even if other matching signals (such as email or phone) would normally trigger a merge.

## Why use this setting

This setting preserves the integrity of customer profiles when each customer has a distinct unique ID in your system. It's useful when your source of truth (for example, a CRM or loyalty platform) guarantees that two different IDs always represent two different people, and you don't want Maestra to combine them.

<Note>
  The block only applies to customers whose unique IDs differ. Profiles without an ID, or profiles sharing the same ID, follow Maestra's standard merging rules.
</Note>