give me solution, When we have create Product category on Quickbook sandbox account but Quickbook response as a product type 'service'.

Thanks for reaching the QuickBooks Community page,@Synconics.

Allow me to provide a few information about the product category is changing to service.

QuickBooks Online (QBO) is only a receiver of the data that is transmitted. It only depends on the data provided by your third-party app.

In case you'll want to learn how to add everything you buy and sell in your inventory into QuickBooks. You can check this article for more guidance: adding inventory products in QuickBooks Online.

Also, to check the status of your inventory, you can check this article to learn more: Use reports to see your sales and inventory status.

If you need additional help, feel free to reach out to me. I'm always here to provide further assistance with anything QuickBooks related. Have a good one!