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Addon SKU on my Chargebee site has not been synced to Shipstation. Why?
How to map Chargebee addons with Shipstation SKU?
This could happen if the API name used for the SKU field under the Addon is not named correctly.
You may want to have an Inventory SKU field for every item in your Chargebee Product Catalog which you wish to map to ShipStation. To do this, create a custom field at the plan and addon level with the API name as cf_inv_sku. This field would then be automatically mapped to the SKU field at the line item level in ShipStation.
The mapping for custom fields plan at price[cf_inv_sku] or addon price[cf_inv_sku] or charge price[cf_inv_sku] happens based on the API name of the custom field and it is essential to have the API name set to cf_inv_sku.
These fields are mapped to ShipStation depending on whether order_line_items[entityType] is plan or addon or charge respectively. Within the Custom fields, Field Label and API Name must be [cf_inv_sku].
Otherwise, order_line_items[sku] is mapped to ShipStation.
Related articles and Documentation
Shipstation integration field mapping