If you're talking about Destiny 2, Destiny 2 Forsaken - Legendary Collection is the same exact price that Destiny 2 would be if it was sold stand-alone. Because of the price equality and the fact that Destiny 2 Forsaken - Legendary Edition comes with Destiny 2, it is not sold in the store on its own anymore (there's no point in having two items at the same price and one of them comes with more stuff); so, you must purchase a bundle to get the digital version of the base game. If the only one you're seeing in the Microsoft store is the more expensive Complete Collection, then I suggest searching for "Forsaken Legendary" to get to the bundle that is the proper price. You will not be losing money or getting a discount because of you already owning the DLC, as it'd be the same price if the base game was still available digitally on its own. If you're in the US, you can use this link: https://www.microsoft.com/en-us/p/destiny-2-forsaken-legendary-collection/c25jldq0wsf4