First of all, ensure that you’ve created the units; if not, please refer to:
ZiiPSI-How to Add Units of Measurement – Zii Help Center (ziicloud.com)
Go to “Product” under “Products”.
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Double click the item that you want to modify.
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Then, on the item modification page, you can change an item’s minimum unit. (Only when the item has not been sold yet.)
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If there are more than one unit for this item, you can change on “Mutil-Unit” section.
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Then click “Save” when the changes are done.
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