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- Open the "Master data" menu and select "Category" to open the category list. Then, use to "Create" button to create a new category.
- Enter the new category "L1" and leave the "Parent Code" blank. (Cause it will top level of the item category).
- Enter the new category of level 2 and select the "L1" as of "Parent Code". Click the "Save" button to complete the process.
- Create next level of category and assign former level category to build up multi level category.
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