Pricing Rule only executes once per document?

I have a group of finished products that have a 1+1 scheme going on for distributors (a customer group). I have created a pricing rule for this scheme and have chosen Brand, item group and all possible options to bulk apply the scheme to all the products encompassing the applicable products.

It works perfectly fine the first time I select any applicable product in an invoice, sales order or proforma, etc. Unfortunately, when I selected another applicable product in the same document, the free item does not show up and the price automatically becomes zero despite the listed price being correct.

Any idea what is going on and how to enforce the scheme correctly? I have tried uploading an image to show the issue. If I disable the pricing rule, pricing for everything fetches correctly.

Never mind I saved the draft and it fetched the pricing and the free items. As I suspected, it seems only the preview triggers once. The scheme itself executes properly once the document is saved. Will test it more though and update the topic I face additional problems.