I don't know EXACTLY who to go to however I do feel that if posted here it can get to the right person. As part of the Bing rewards system you can claim ancient coins when you reach 1,700 (150 coins) 5,100 (550 coins) 8,500 (1000 coins) in my research on the matter in order for you to claim the coins you would need the Xbox/Microsoft store version of the game, which is all well and good, if this version of the game was the only version that existed but as of now there is a steam version, PS version and an Xbox version of the game.
As of now for me to claim the coins I would have to either go round my friends house and log into his version of the game on his Xbox (which until Microsoft decide that you can't log into a game if you haven't got a licence for it is an option) or I have to get the Microsoft store/Xbox version of the game, which would cost me and extra £40 or £10 per month minimum. It's worse for people who don't have a friend with an Xbox however as they can't redeem it, maybe instead of having it the way it is you can introduce a "redeem code" option in the game and have it done that way where you get a code you can paste in and get the coins that way, or have it so that when you redeem it goes directly to the account and you just have to log in to any version of the game to redeem
