Only the Send Inventory Levels Action will work for adjusting inventory levels. The unique identifier is the SKU field in WooCommerce.
1. Sync inventory only Standard Products (Send Standard Levels Inventory Action)
2. Sync inventory only Matrix Products Action. (Send Matrix Inventory Action)
Note: simple update price or inventory to give the item a new time_stamp.
See example below for WooCommerce (non multiple locations) inventory sync.
Simply view your TASK Activity logs and Upload the Full log to a Support Ticket for further assistance.
Also, see the following help article for list of Activit Log messages.
Do you have decimals in your inventory? If so, try this plug-in below on github.
https://github.com/woocommerce/woocommerce/issues/27375
If you’d like to purchase a support package, you can do so here.
If you have further questions, please post a ticket in our Help Desk