If a product that you don't stock is appearing in Google, there are two reasons why this might be:
The product's quantity is incorrect in your Point of Sale
The product's information needs editing/correcting
Find the product
The first thing to do is identify the product that's appearing incorrectly on Google. You can find the product's barcode in your Point of Sale, or search for the product by name in your NearSt dashboard.
Update quantities and product information
From here, check the product in your POS and make sure it is set to out of stock. If the quantity is correct, the product information will need to be updated in the NearSt dashboard.
To do so:
Sign into the NearSt dashboard.
Go to Inventory → Manage items.
Search for the barcode or product title.
Click into the product to edit it, or hide it from one or more channels.