An Inventory Valuation Summary report summarizes the quantity, average cost and extended value of each of the inventory quantities and provides a total inventory valuation. To properly give you the best answer to your question, can you provide me with additional screenshots of the report? I'll be able to narrow down the issue when looking further into the report from your side. In the meantime, here's an extra article that can give you some information about the Inventory Valuation Summary report.
Touch base with me after getting the screenshots. I want to make sure that you're able to get this resolved as soon as possible. I'll be waiting for your response.
There are times that your browser is full of frequently-accessed page resources, thus causing websites, like QuickBooks Online (QBO), to act weirdly. This can be the reason why your Inventory Valuation Summary report display's an amount when the quantity on hand is 0.
We can start by logging into your QBO account using a private browser so we can isolate this issue. To do so: