multiple deals are not applying in same transaction

Hello Experts,

I am using customer engagement cloud service 18.

I created two deals BOGO and two separate promotion for each deal ,each deal is having different items. the deals are the same for both of them (buy one get one free).

Now if we scan two items from each deal, the BOGO is not getting applied. unless we use same items from same deal.

Now how do I make these two promotions work together in same transaction.

meaning scan one item from the first BOGO promotion and other item from second BOGO promotion should apply (buy one get one free).