Quantity error with adding multiples of the same product

We have a perennial problem with some of our product pages that is driving us all mad. When a customer tries to add more than one item of the same variant to their cart a pop-up loads saying only X amount of product is left. The customer could only want to order 2 and the pop-up says ‘only 23 left’, but it doesn’t let the items be added to the cart. The only way they can increase the quantity is add one to the cart and then update the quantity there.

I’m having the same problem. Did you figure out a fix for this?