I noticed today that when you don't enter SKUs for ALL your variations in a listing, Etsy will randomly choose one from another variation and enter it - leading to the wrong product being fulfilled from our POD. The result is the customer gets the wrong item.
It is common for certain POD items to be left blank and SKUs added as they sell. Also, if a design needs to be personalized, I will leave that space blank on the personalized option.
Please look into this. Thank you.