Common Issues

Connection issues

Authentication fails when I enter my API key

Zoho Books uses a combination of an API key (auth token) and an Organization ID. Make sure you've entered both correctly — a missing or wrong Organization ID will cause the connection to fail even if the API key is valid.

You can find your Organization ID under Settings > Organization Profile in Zoho Books. If you have multiple organizations, confirm you're using the ID for the right one.

My API key stopped working after it was working before

Zoho auth tokens can expire or be invalidated if you change your Zoho account password, enable two-factor authentication, or revoke tokens from the security settings. Generate a new auth token from your Zoho account and update the connection in Coupler.io.

Missing data

Some invoices or bills are missing from the export

Check the start date setting in your data flow. If it's set too recently, older records won't be included. Adjust the start date using the date picker to extend the historical range.

Also confirm that the missing records aren't in Draft status — some Zoho Books entities filter out drafts by default depending on API behavior.

Line item details aren't showing up

Coupler.io pulls top-level entity fields. Detailed line items may not be included in the standard entity export. If you need line-level data (e.g., per-item amounts on an invoice), check whether the data appears in the fetched columns — it may come through as nested fields or may require a separate data flow configuration.

Permission errors

I can connect but some entities return no data or an error

The Zoho Books user whose API key you're using must have permission to access the entities you're pulling. For example, a user without access to Banking or Journals won't be able to export those entities. Use an admin account's API key, or ask your Zoho Books admin to grant the relevant permissions to your user.

Data discrepancies

Totals in Coupler.io don't match what I see in Zoho Books

This is often a currency issue. Zoho Books stores amounts in the transaction currency, not necessarily your base currency. If you're aggregating totals across multiple currencies without conversion, the numbers won't align with Zoho Books' converted totals.

Also check whether you're comparing the same date range — the start date in Coupler.io controls which records are included.

Transaction counts differ between the Transactions entity and other entities

The Transactions entity reflects all ledger-level entries, which can include system-generated entries not visible in other views. It will naturally show more rows than, say, the Invoices entity alone. Use filters or the Aggregate transformation in Coupler.io to group transactions by type if needed.

Rate limits

The data flow fails or slows down with large exports

Zoho Books API has rate limits that vary by plan. If you're pulling large volumes of data (e.g., all Transactions over several years), the sync may hit these limits and slow down or fail. Try setting a more recent start date to reduce the data volume per run, or split large exports into separate data flows by entity.