The Calculate Tax Button Creates A Credit Invoice Line For The Tax But This Line Is Missing The Invoice Line Item Field
When a credit invoice is created and tax is calculated, the tax line does not correctly reference the invoice line item. This is a known defect in Order & Inventory Management. Manually populating the invoice line item and using "Push to AC" serves as a workaround. Upgrading to a newer version of Order & Inventory Management will resolve the issue.