This discount is random. Sometimes it's there, sometimes not. The regular offer we all get are two more premium games to play as long as you have the H+ subscription. I have a 1 year subscription and in 9 months I've had the discount a few times, but not every month. Possibly it's different for you but this is my experience. It's possible it was a limited offer. I haven't looked into it so much as I've been busy with the 2 games offered each month. Your situation might be different so maybe contact support to be sure it's not an error.
