1) Complete the steps below only after Deliverr has received your products into inventory. If Deliverr is set to fulfill your products before, then this may result in backorders in Shopify.
2) This process is only for when you use Deliverr to fulfill all of your orders. If you plan to use Shopify's multi-location feature to fulfill some orders with other 3PL (third-party logistics) partners, or if you plan to fulfill international orders, then please contact our support team for more instructions on how to setup Shopify multi-location.
Log in to your Shopify store.
In the left sidebar navigate to Products and find or select the product.
Scroll up from the Fulfillment Service dropdown to the Inventory managed by dropdown, and select Deliverr.
At the top of the screen, select Save your changes.
Set up auto-fulfillment
Make sure that auto-fulfillment is turned on so that orders are automatically forwarded from Shopify to Deliverr.
In Shopify, go to Settings > Checkout > Order Processing. Under "After an order has been paid", select "Automatically fulfill the order's line items", as shown in the screen shot below.
Save your changes at the bottom of the screen.