I have a prestashop module which has a custom setting for quantity such that if there are a few combinations of a product - all having same quantity - when one combination is purchased then the same quantity is reduced for all combinations. eg:(https://i.stack.imgur.com/ZjCf3.png)
I have successfully achieved the necessary functionality here ie. if a pack of 10 is purchased then the qunatity of all three combinations here image) is changed to 2592 and similrly for all combos.
Now this works fine for all payment modules except ps_checkout -> paypal. If anyone has any idea on how to solve this issue please share.
I tried to debug the module but it wasn't fruitful since I couldn't pinpoint to the exact part where order is placed successfully or product quantity is updated