Help me with fulfilling orders from different locations depending on inventory

We have products that sometimes we stock at our main location but if it isn’t currently stocked then we send the fulfillment request to the vendor. So I wanted to configure this in Shopify using custom fulfillment services. https://help.shopify.com/en/manual/fulfillment/fulfilling-orders/custom-fulfillment

I set up a custom fulfillment service called Evan Inc. and assigned it to a test product, along with our main location. I set the main location’s stock to 0. I made sure to uncheck “Continue selling when out of stock.” My hope was when I fulfilled an order it would automatically fulfill it using the location that has stock, Evan Inc.

Unfortunately it didn’t work like that. I created the order and it automatically selected 118 W Burlington as the fulfillment location, in fact I don’t see a way I can even manually change that in the order. I went back and checked inventory for the product and sure enough the stock level at 118 W Burlington was now -1.

Is there a way to configure order fulfillment to automatically use the location that has stock?

I did find how to change the location manually in the order but I want it to be done automatically.

I figured it out. You have to go to Settings > Shipping and Delivery, go into the profile you’re using, and add all the possible locations there.