I have looked everywhere for this bug and I cant find anything about... Even on facebook groups people say they've never seen it... Here is my situation:
A customer places an order and only the products in this order get its quantities duplicated. To explain even better, it is not the whole order that duplicate and I get 2 orders in my dashboard. It is only the quantity of each product in the order.
https://prnt.sc/vteu4d So lets say in this order the customer placed as the quantities in RED but the system changed the quantities to what is showing in the screenshot (system).
There's no payment method in the website, we use the native "Cash on Delivery" and the customer pays in cash at collection or delivery.
Has anyone ever been through this before? Any idea on how to fix it?

Thank you everyone !! <3
EDIT-----------------------------
Opencart version: 3.0.3.3
PHP Version 7.3
Template: https://themeforest.net/item/safira-res ... e/25673080
Extensions installed: https://prnt.sc/vti92q the only one I installed is the one with the red arrow, it means "Minimum amount required" it has to be at least 20e order.