[QST] Recommending items from transactions data

[chakra1166]

Hi,
I have a transactions data of user and items. Now I want to build a two tower model using this transaction data. Now my question is should I duplicate customer x item combinations based on number of transactions or just create one row per customer x item. If I just create one row how do I tell the mode to differentiate between a item that is purchased 5 times vs 1 time by the same customer

Thanks in advance