Zend certified PHP/Magento developer

How to keep ‘In stock’ even though the qty is 0 after a csv file import

We are currently running a cron job to import sku, qty, and price every 30 min.

If the qty for a product becomes 0, the stock status changes from ‘In stock’ to ‘Out of stock’ automatically, ‘Add to Cart’ button is gone on the product page, which makes customers impossible to add the part to the cart.
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I also allowed the backorder in the configuration but no use.

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I’d like to display the Add to cart button even though the qty is 0.

Can you please share your wisdom?

The magento ver. is 2.3.4.