Send Amp Back in Stock Restock Alerts via LINE

This feature lets you send LINE restock alerts to the customers who signed up for back-in-stock notifications through the "Amp Back in Stock" Shopify app. When Amp sends a restock notification, a Lumo workflow delivers a product-card message over LINE.

What you can do with the Amp Back in Stock integration

"Amp Back in Stock" is a Shopify app that lets customers sign up for a restock alert on out-of-stock products and notifies them when the item returns. With this integration, you can also send a LINE restock alert at the same time Amp notifies the customer.

Adding LINE on top of email and SMS makes the alert more likely to be seen and to lead to a purchase. The message can be a product card with an image and a button, and you build the content and flow freely in a Lumo workflow.

What you need to use this feature

To use this feature, both Shopify and Amp must be set up. Check that all of the following are in place.

Matching is done using the email address or phone number registered in Amp. Only customers whose Amp email or phone is linked to their LINE on Lumo will receive the LINE restock alert.

Setup overview

Setup has three steps: configure a webhook in Amp, register your Amp API key in Lumo, and build a workflow.

1. Set up a webhook in Amp — register the endpoint URL that Lumo shows into Amp's webhook settings
2. Register your Amp API key in Lumo — enter your Amp API key on Lumo's Shopify integration settings screen
3. Build a workflow that sends the restock alert — use "Restock (Amp)" as the trigger to send a product card over LINE

Each step is explained below in order.

Setting up a webhook in Amp

First, set up a webhook in Amp so that Lumo can receive the signal when Amp sends a restock notification.

1. In Lumo, open "Customer data" > "Shopify", find the "Amp Back in Stock" card, and copy the "Webhook URL"
2. In Amp Back in Stock, open "Settings" > "Webhooks" and create a new webhook
3. Paste the URL you copied in step 1 as the destination URL
4. Choose "notification/sent" as the event (this fires when the restock notification is sent to the customer)

Lumo triggers restock notifications only for "notification/sent". The signup event "notification/create" does not send LINE messages. Amp test webhooks check the connection without sending a LINE message.

Note that Amp webhooks are available on the Medium plan and higher. If you can't find the webhook screen, check your Amp plan.

Registering your Amp API key in Lumo

Next, register your Amp API key in Lumo so that Lumo can verify that incoming webhooks really come from Amp.

1. In Amp Back in Stock, open "Account" > "API" and find your API key
2. In Lumo, open "Customer data" > "Shopify" and show the "Amp Back in Stock" card
3. Paste the Amp API key into the "API key" field and select "Save"

The API key is used to verify that a webhook arriving from Amp is genuine. Once saved, the card shows that a key is registered.

Building a Workflow that sends the restock alert

Finally, build a workflow that sends a LINE message when a restock happens. Use "Restock (Amp)" as the trigger and connect an action that sends a product card.

1. Create a new workflow in Lumo and choose "Restock (Amp)" as the trigger
2. Add an "Auto-Send Message" action and select a message that contains a restock product card
3. Publish (activate) the workflow

The "Restock (Amp)" trigger is only available when Shopify is connected. It appears alongside the other triggers marked with the Shopify icon.

About the action that sends the product card

To send a restock product card (a card with the product image, name, and a button), add an "Auto-Send Message" action and select a message that includes a card-type "Product" message. Set the product source to "Trigger products" so the card for the restocked item is built automatically.

Tapping the button on the card opens a page with the restocked product already in the cart (the same purchase path as the restock email). If the variant can't be identified, the product page opens instead.

Be careful which action you choose. The "Send LINE Notification Message" action doesn't render the product card correctly and falls back to text only. To send a product card, always use "Auto-Send Message".

How "back in stock" is detected

The Lumo restock workflow starts when Amp sends a real restock notification and Lumo receives it. This integration does not independently detect changes in inventory levels.

If increasing inventory does not produce a LINE message, check Amp's notification settings and delivery history to confirm it sent a notification to that customer. Then check that the Lumo workflow is active and the customer has linked LINE.

The image and price on the LINE product card come from product data that Lumo syncs from Shopify. If the product data has not been synced yet, the image or price may not appear.

When things don't work

When restock alerts don't arrive, the cause is usually the customer's LINE linking or the Amp-side settings. Check the following in order.