X1 Free with gold is not free.

Try re-downloading your profile and try again.

For the 360, I suggest searching the store for Dark Souls and download it that way. It should say
free if you are an xbox live gold member.

As for the Xbox One, I'd keep checking
here for updates on when the June Games With Gold will be available. It just says June so as there is no specific date, it could be any point in June. There is also currently no news on whether or not the games will be available
as a free download for the whole month or half a month each like the 360. I am hoping there will be more details over the next couple of days.

Major Nelson posted an article about the Games With Gold program on the Xbox One.

majornelson.com/.../xbox-live-games-with-gold-for-june-2014

In it, Phil Spencer says that the games will be available after the release of the June update. Please be patient, the games will be available to all Gold members soon.

I have several times and still the same thing.

I may not have a 360 yet but i have been able to get the 360 games that was free from the gold membership for the last month and half.