Variable product inventory not deducting

Yes, the orders have been paid for successfully, and for the correct amount as well.
Strangely, nothing changed from when it used to work, til now. We didn’t update anything, nor did we touch the site from the time it used to work, until we received our first order with the variable product not deducted.

Sure, so for simplicity, this is the screenshot of the order page of an order with 1 item, which is a variable product.
There’s no product deduction at the side, and the variation purchased isn’t shown:
https://snipboard.io/hCDZEF.jpg

I don’t have payment gateway logging enabled, but here’s a screenshot of this transaction in my payment gateway merchant portal, which shows the variation purchased:
https://snipboard.io/d2YZ7p.jpg

And this is the transactional email I received, which also shows the variation purchased:
https://snipboard.io/bsrUJZ.jpg

Also, this is an example of an order that has both simple and variable products. From the order notes, you can see that the simple products are deducted, but not the variable product (the middle product):
https://snipboard.io/wI1Kcj.jpg

Thanks!

Yes, I have manage stock enabled for everything. However since last posting, this still happens for random orders, not all the orders. I have already disabled and enabled plugins to check for conflict, but as it doesn’t always happen, it’s difficult to determine whether there’s a plugin conflict.