Discount and coupon conflicting together?

-- HikaShop version -- : 4.2.1
-- Joomla version -- : 3.9.12

Hello,

I have a default discount of 20% set in place for a certain user group

Now I have set a coupon code with 30% discount for a product

When I set the coupon code to "override discounted products" this is what I see in the cart when I apply it

29,60 € -20%
Coupon code -1,48 €
Total 28,12 €

Not sure what's happening,
I am testing with a user which has the 20% fixed discount I was talking about

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When I set the coupon with "standard behavior" this is what I see instead

29,60 € -20%
Coupon code -8,88 €
Total 20,72 €

basically now the product is being discounted of 20% and then another 30% discount is being applied because of the coupon code used

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Instead this is what I was expecting to happen

The product normal cost is 37 €
The user default discount of 20% is being overwritten whne using the coupon code

Product cost 37 €
29,60 € -20% (this is being overwritten by the coupon code setting)
Coupon code -11,1 €
Total 25,90 €


Any idea how to achieve the above example?

thank you

Thank you, I understand