Transferring of Games Across AppleID

Hi Guys,

I Purchased Star Wars Knights of the Old Republic 1 & 2 on my Mac and recently wished to download them on my Ipad aswell, I am logged in to the same AppleID on both devices but I would be required to pay for the games again to play them on my Ipad. I know that game purchases do transfer from one device to another across the same AppleID as I also purchased Geometry Dash on my Mac and had no problems with downloading it on to my Ipad with no additional charges. Do any of you know any simple resolutions to this issue or would it be best to make contact with Apple about this problem so that they can hopefully assist me?

Many thanks,