Troubleshooting sequence errors and variable blocks

Last updated: April 1, 2026

When sequences fail to send or become blocked, the issue is often related to variable formatting errors or template configuration problems. Here's how to identify and resolve these common sequence issues.

Check for template syntax errors

The most common cause of blocked sequence enrollments is incorrect variable syntax in your email templates. Variables should be formatted with double curly braces like this: {{variable_name}}

Common syntax errors include:

  • Extra brackets: {{{{variable_name}}}} instead of {{variable_name}}

  • Missing brackets: {variable_name} instead of {{variable_name}}

  • Incorrect spacing: {{ variable_name }} instead of {{variable_name}}

To fix syntax errors:

  1. Review your sequence template for any variable formatting issues

  2. Ensure all variables use the correct {{variable_name}} format

  3. Remove any extra brackets or incorrect spacing

  4. Save your template changes

Resolving blocked enrollments

When enrollments are blocked due to template errors, you have two options for resolution:

Option 1: Fix individual enrollments

You can manually edit blocked enrollments in your outbox to correct missing or incorrectly formatted variables. However, these changes only apply to that specific enrollment - you'll need to edit each blocked enrollment individually.

Option 2: Fix the template and re-enroll

For a more efficient solution when multiple enrollments are affected:

  1. Fix the variable syntax errors in your sequence template

  2. Remove contacts who haven't received emails yet from the current sequence

  3. Re-enroll these contacts in the corrected sequence

Preventing future sequence errors

To avoid sequence blocks and errors:

  • Always test your sequences with a small group before large enrollments

  • Double-check variable syntax before saving templates

  • Ensure your CRM integration is properly syncing contact data

  • Verify that required contact fields are populated before enrollment

If you continue experiencing sequence errors after checking variable syntax and template configuration, the issue may be related to your CRM data integration or contact field mapping.