Problem with the tiered discount

Hello,

I have a problem with tiered discount that was set to work as cart line fee for all products if a certain payment method is selected.

You can see short demonstration video here > https://drive.google.com/file/d/1TH6Ld1YitJuSN6LZQU5QnkU7AvW6MPG3/view?usp=sharing

The problem is as follows:

1. base price for 2 products is 6,2 €
2. after selecting payment method that has 4% fee, price for both products is in total 6,45€ which is ok
3. after selecting the payment method that has no fee connected, price gets back to 6,2 € which is ok
4. if you select after that payment method with 3% fee, price goes to 6,63€ which is wrong (its 6,2€ + 4% + 3%), price should be 6,39€
5. after selecting the payment method that has no fee connected, price gets back to 6,44 € (6,2€ + 4%) which is wrong because base price is 6,2€

After this point, there is no way to get back to original price of 6,2€, price always stays at 6,44€ which is base price + 4%

How should I fix this problem? Also, how can I remove crossed original price in cart page? I don’t have any discounts applied.

Thank you!

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