When new SKU pass from integration platform sales line, the SKU mapping in BC maybe missing, using the following way to resolve the mapping error 

Step-by-step guide

  1. Go to "Ecommerce Order List" via menu
  2. Under Ecommerce Order List function, Find "Related" > "Resolve Line Errors"
  3. Under Ecommerce Order Line List, select the "Item No." related to the error line, once the Item No. selected, it will generate the Sales Line in next schedule and remember the SKU in next time