FH3 FH4 ultimate bundle

I found a FH3+FH4 ultimate bundle redeem code selling for 50 USD. but I already have a FH3 ultimate.
If I redeem it, what’s going to happens? I feel like it’s will have some game’s duplicating problem.
Is it gonna be like Steam (duplicate game become a gift) or I just can’t redeem it or redeem and get FH4 ultimate with no problem at all?

You should be able to redeem it and get FH4 Ultimate without issue. I am not aware of any game duplicating issues on Xbox, unless you own a physical copy and buy digital, then both copies will be listed as installed, but you can install one without affecting the other, afaik.

Are you sure it’s not 2 codes
If its just one you are basically wasting the one you already own…unless you own it physically