How to sync Shopify and Amazon items SKUs?
Upon installation, All of the items from Shopify will be available by default in the Automated Multi-Channel Fulfillment app. However, when you will enter your correct Amazon FBA credentials it will pull the Amazon items into the app.
If Shopify item SKUs and Amazon item SKUs are the same, then the app will automatically map the items from Amazon FBA and Shopify. However, In case if you want to map a Shopify item SKU with Amazon FBA SKU (having different SKUs) then you are required to map them manually by clicking update button.
NOTE: It takes max of 6 hours to pick the new listings automatically, but if you need to do before you can click the button Sync Manually on Item mapping page to speed up.
Note: If you map Shopify SKU with wrong Amazon SKU or you don't map the Shopify SKU with Amazon SKU then this will make the Shopify Inventory to 0. If you want to prevent the inventory change to 0 then you can archived the item , that particular item inventory will not alter.