How to Catch Shopify Overselling After an Order Is Paid?

Overselling can happen when a paid Shopify order contains a tracked product variant whose total inventory has dropped below zero. In this Shopify Flow tutorial, we use Shopify Sidekick and FlowSend to build an automated overselling alert for your operations team. The workflow starts when an order is paid, checks whether any ordered variant has inventory tracking enabled and negative inventory, and prepares one consolidated FlowSend email listing the affected products, SKUs, quantities, and stock levels. The demonstration remains inactive. No emails are sent, and no inventory, orders, or fulfillment data are changed. This video is brought to you by FlowSend — the Flow Mail app. Send branded Shopify Flow emails using your own SMTP, Liquid templates, and delivery logs. Try FlowSend: https://apps.shopify.com/flowsend What You'll Learn ✅ Use Order paid as the workflow trigger ✅ Check whether inventory tracking is enabled ✅ Detect variants with inventory below zero ✅ Exclude untracked variants and inventory at zero ✅ Include product names, SKUs, and quantities ✅ Send one consolidated FlowSend operations email ✅ Use Liquid to display only matching products ✅ Keep the email action outside line-item loops ✅ Review and save an inactive workflow draft Prompt Used Copy and paste this into Shopify Sidekick: Create an inactive Shopify Flow draft now named “DEMO | Paid order overselling alert”. Do not ask questions or request permission. Start with Order paid. Detect whether any ordered variant has inventory tracking enabled and total inventory quantity below zero. Send one FlowSend staff email per order to demo@example.com, listing matching products, SKUs, ordered quantities, and verified inventory values. Keep the email outside line-item loops. Clearly state that inventory is evaluated when the workflow runs and is not proof of availability at the assigned fulfillment location. Inspect actual fields and variables; prefer inline content and create no separate template. If tracked-inventory eligibility cannot be verified, report that check as blocked. Leave inactive, send nothing, change no inventory or orders, and report actual creation status. Workflow Overview Trigger: Order paid Condition: At least one order line item satisfies BOTH: • Inventory tracking is enabled • Total variant inventory is below zero A quantity of zero does not qualify. Both checks must apply to the same variant. True branch: FlowSend — Send Transactional Email Demo recipient: demo@example.com Email includes: • Order name • Matching product titles and SKUs • Ordered quantities • Current inventory values False branch: End without sending an alert. The FlowSend action stays outside the line-item loop, so affected products appear in one email per qualifying workflow run. Important Notes • Replace demo@example.com with your operations inbox. • Test your FlowSend SMTP connection and verify all Liquid variables. • Test positive, zero, negative, tracked, and untracked inventory. • Test orders with multiple matching and non-matching items. • Confirm only qualifying products appear in the email. • Total inventory does not prove availability at the assigned fulfillment location. • This alert does not reserve inventory, modify orders, or change fulfillment. • The workflow remains inactive during the demonstration. No emails are sent. Timestamps 0:00 - FlowSend Introduction 0:13 - Overselling Alert Overview 0:50 - Verify Shopify and FlowSend Fields 0:59 - Review the Generated Workflow 1:34 - Add the Inactive Draft to Shopify Flow 1:52 - Validate and Save the Workflow 1:58 - Review the Workflow Canvas 2:17 - Order Paid Trigger 2:36 - Check Tracked and Negative Inventory 3:19 - Configure the FlowSend Alert 4:02 - Inventory and Location Limitations 4:20 - Keep the Workflow Inactive 4:35 - Pre-Activation Checklist 4:42 - Final Workflow Summary Resources FlowSend: https://apps.shopify.com/flowsend Shopify Flow: https://apps.shopify.com/flow Shopify Flow guides: https://fixmystore.com/shopify-flow Shopify Sidekick guides: https://fixmystore.com/shopify-sidekick Shopify Flow conditions: https://help.shopify.com/en/manual/shopify... Tags Shopify Flow, Shopify Sidekick, FlowSend, Shopify Overselling, Overselling Alert, Negative Inventory, Inventory Tracking, Order Paid, Shopify Automation, Ecommerce Operations, Inventory Management, Fulfillment Automation, Liquid Variables, SMTP Email, Shopify Tutorial, FixMyStore #ShopifyFlow #ShopifySidekick #FlowSend #ShopifyAutomation #InventoryManagement #EcommerceOperations