# Template mismatch

When previewing an email template or sending/scheduling a campaign, Mail Rocket validates the selected template in the background. If any variable in the email template is missing from your contact list, it will display a "Mail Merge Issue - Template Mismatch" warning.

{% hint style="success" %}
If you feel the email template is normal, feel free to continue sending emails.
{% endhint %}

<figure><img src="https://2708547714-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FQ2Oq7wXz6MEOz8Y4u8DP%2Fuploads%2Fba85OnJ83InoDJ9B1BSh%2FScreenshot%202024-05-21%20at%208.18.43%20PM.png?alt=media&#x26;token=b6569404-065c-425b-b84e-19d91b3b039e" alt=""><figcaption></figcaption></figure>

### How to fix "Empty variables detected"?

In the above screenshot, empty variable detected is **{{ namp }}.** This means column **"namp"** is missing from your contact list.

The screenshot below shows the initial contact list.

<figure><img src="https://2708547714-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FQ2Oq7wXz6MEOz8Y4u8DP%2Fuploads%2F9hWF0hVdzVGssOfjf8s9%2FScreenshot%202024-05-21%20at%208.33.27%20PM.png?alt=media&#x26;token=de44481f-a730-42c1-bd81-bdb0ff217998" alt=""><figcaption></figcaption></figure>

Add a column called **"namp"** along with its values as shown in the screenshot below.

<figure><img src="https://2708547714-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FQ2Oq7wXz6MEOz8Y4u8DP%2Fuploads%2Fx3trf9IXN9YtV2GARqzE%2FScreenshot%202024-05-21%20at%208.34.29%20PM.png?alt=media&#x26;token=ff396612-9b3f-4f43-9af9-e9c60f5f17ee" alt=""><figcaption></figcaption></figure>

After all the columns needed are added, restart Mail Rocket.