Skip to content
STOQHelp center
Open STOQ

Fix Klaviyo emails not sending after flow verification

Your STOQ flow verifies with a green check but customers don't get the email. Here's why, and how to fix it.

Last updated

When STOQ verifies a Klaviyo flow, it checks that a flow with the right name exists. It doesn’t check what’s inside the flow, so a flow can verify successfully and still fail to deliver. These are the three usual causes.

Find why a message was skipped

Section titled “Find why a message was skipped”

Klaviyo records a reason for every message it doesn’t send, so start here to see which cause below applies before changing anything.

  1. Open the flow’s email in Klaviyo

    In your Klaviyo dashboard, open the flow triggered by the STOQ metric, for example Back in stock alert (STOQ), then click its Email action.

  2. Open the message’s analytics

    In the email’s panel, click View details to open its performance analytics.

  3. Open Recipient activity and filter to Skipped

    Open the Recipient activity tab, then set the activity filter to Skipped. Each skipped recipient shows a reason, such as Skipped: Catalog Item Unavailable.

    Klaviyo’s Recipient activity tab for a Back in Stock Email message, with Skipped selected in the left list and the activity filter set to “Skipped: Catalog Item Unavailable”, listing the recipients whose alert was skipped

Match the reason to its fix below:

Skip reason in Klaviyo What it means
Catalog item not available (or similar catalog wording) Your template uses Klaviyo catalog variables. See The template uses catalog variables.
Skipped by Smart Sending See Smart Sending is skipping the email.
No skipped recipients at all The message isn’t being triggered. See The flow is triggered by the wrong metric.

Smart Sending is skipping the email

Section titled “Smart Sending is skipping the email”

The Klaviyo Flows editor for the flow named ‘STOQ - Back in stock alert (STOQ)’ marked Live, with the ‘Email details’ panel open to its Settings section showing a checked ‘Skip recently emailed profiles’ checkbox (captioned ‘Smart Sending will skip anyone who received an email within the last 16 hours’), an unchecked ‘Enable UTM tracking’ box, an Additional filters area with an ‘Add filter’ button, and ‘Unsaved changes’ with Cancel and Save buttons at the bottom; with markers: 1 on the ‘Skip recently emailed profiles’ checkbox, 2 on the Save button.

Klaviyo’s Smart Sending skips a profile that was emailed recently (within about 16 hours). Because a customer may have just gotten another email from you, the back in stock alert gets suppressed.

Fix: Open the flow’s Email action settings and turn off Skip recently emailed profiles (Smart Sending) for that action. Back in stock alerts are time-sensitive and explicitly requested, so they should always send.

The template uses catalog variables instead of STOQ variables

Section titled “The template uses catalog variables instead of STOQ variables”

If your template pulls product data from Klaviyo’s catalog lookup blocks (like catalog_item.title), Klaviyo may skip the send when the product reads as out of stock in its catalog, which is exactly the moment a restock alert should fire. The same cause often shows up as a catalog error in Klaviyo, or the product name, image, and price rendering blank, because STOQ sends the details on the event rather than through Klaviyo’s catalog.

A Klaviyo email template text block containing a catalog lookup, {% catalog event.VariantId integration=‘shopify’ %}catalog_item.title{% endcatalog %}, instead of a STOQ event variable

Fix: Replace catalog references with STOQ event variables, for example use {{ event.product_title }} instead of catalog_item.title. STOQ sends the product details on the event, so no catalog lookup is needed. See Reusing your own or a Klaviyo template for the full swap, and Personalize Klaviyo back in stock emails for every variable.

The flow is triggered by the wrong metric

Section titled “The flow is triggered by the wrong metric”

The Klaviyo Flows editor for a Draft flow named ‘STOQQ’ with the ‘Select a trigger’ panel open on the ‘Your metrics’ tab (alongside Recommended and All triggers tabs), listing metrics under the ‘STOQ: Preorders, Back in stock’ integration heading: Back in stock alert (STOQ), Back in stock reminder 1 (STOQ), Back in stock reminder 2 (STOQ), and Back in stock SMS alert (STOQ); with markers: 1 on ‘Back in stock alert (STOQ)’.

A flow built on Klaviyo’s native Back in Stock metric won’t fire, because STOQ sends its own metric.

Fix: Rebuild the flow on the STOQ metric that matches your connection: Back in stock alert (STOQ) on an OAuth connection, or the Stoq - prefixed metric on a legacy API key connection. A flow’s trigger can’t be changed after creation, so create a new flow with the correct metric.

Check your setup

Section titled “Check your setup”

The STOQ app back in stock Sending settings panel with ‘Email platform’ options STOQ, Klaviyo (selected) and Shopify Flow, showing step ‘1. Connect Klaviyo’ marked connected with a green check and a Disconnect button, and step ‘2. Create a flow’ with a ‘Back in stock alert’ card whose Flow name field reads ‘BIS’, a ‘Verify flow’ button and a ‘Send test event’ link; with markers: 1 on the ‘Send test event’ link.

After the fix, use Send test event from STOQ, then confirm in Klaviyo that the flow sends rather than skips. Klaviyo’s flow analytics show whether a message was Skipped and why.

FAQ

Section titled “FAQ”
Verification passed, so why doesn't it send?

Verification only confirms a flow with the right name exists. It doesn’t inspect Smart Sending, the template’s variables, or the send settings inside the flow, which is where these issues live.

Where do I see why a message was skipped?

In the flow’s email, click View details, open the Recipient activity tab, and filter to Skipped: each recipient shows a reason, such as Smart Sending or Catalog item not available. See Find why a message was skipped.

Could double opt-in be the cause?

If a signup hasn’t confirmed and you use double opt-in, the profile may not be eligible yet. That’s expected. See Set up double opt-in.

Section titled “Related guides”
Send back in stock alerts through KlaviyoSet up and verify the flow correctly.
Customize your Klaviyo templatesBuild the email with the right variables.
Personalize with variablesUse STOQ event properties instead of catalog lookups.
Was this page helpful?

Still stuck? Ask Quinn or chat with support