Why Your Make or Zapier Automation Is Failing — Debug Guide

Broken automations are worse than no automations — they quietly fail while you think things are running. Here's how to diagnose and fix the most common issues.

Problem 1: Authentication token expired

The most common cause of automation failures: a connected app's authorization token expired or was revoked. This happens when you change your account password, revoke app permissions, or when the service rotates its OAuth tokens.

Fix: In Make.com, go to Connections and check each connection's status. Re-authenticate any that show errors. Set a calendar reminder to check connections monthly.

Problem 2: Data format mismatch

Your automation expects a date in 'YYYY-MM-DD' format but the source is sending 'April 25, 2025'. This type mismatch silently breaks automations.

Fix: In Make.com, use the built-in formatDate() function to standardize date formats. Use toString() and toNumber() to explicitly convert variable types. Always test with real data, not test mode dummy data.

Problem 3: Empty or null data

If an optional field in your trigger sometimes has data and sometimes doesn't, downstream modules expecting that field will throw errors when it's empty.

Fix: Add a Filter step after your trigger that requires all critical fields to have values. In Make.com, use the ifempty() function to provide fallback values: ifempty(trigger.email; 'unknown@example.com').

Problem 4: Rate limiting from APIs

If your automation fires many times in quick succession, the destination API may reject requests with 429 Too Many Requests errors.

Fix: Add a Sleep module between high-volume actions. If processing many records, use Make's built-in error handling (break the bundle on error) rather than retrying immediately.

Problem 5: No error notification

The most dangerous automation failure is one you don't know about. If your automation fails silently, your business process breaks without warning.

Fix: In every automation, add an error handler route. When a module fails, send yourself a notification (Slack message, Gmail) with the error details. In Make.com, right-click any module > Add error handler > choose 'Ignore' or 'Break' then add a notification module.