You can assign one rebate on one item.
To assign double click on "ITEMS" ICON in Back Office software
search the items (ex. "CAMEL /6.19")
Result: In response you will see all camel with the price of 6.19
select all those camel where you need to apply the rebate
select the rebate from "REBATE PROVIDER" drop down list
and click "APPLY"
Alium Technology Inc.