1336700077762703 is not an Amazon product ID. All Amazon product IDs start with "7777...".
Also, these IDs are not provided by the network or the merchant. These IDs are unique to Datafeedr. This is because many networks do not supply unique IDs for their products.
The IDs that we create are either based on a unique ID that the network provides (if they provided it) or based on the affiliate URL. If either of these things changes, then the ID that we create could also change. But we try as much as possible to keep these IDs from changing.