No such thing as a free lunch.

See:
https://psteamcommunity.yuanyoumao.com/groups/idlemastery/discussions/0/1290691937722380084/
and
https://psteamcommunity.yuanyoumao.com/groups/idlemastery/discussions/0/133257636766989675/

See:
https://psteamcommunity.yuanyoumao.com/groups/idlemastery/discussions/0/1290691937722380084/

Maybe you should ask this guy who has 634 'friends' called jmakela
psteamcommunity.yuanyoumao.com/id/clees42/friends/

Nope, unless you buy 20 copies of the game and make 20 steam accounts and then use Archi's steam farm to get the cards.

Are you using idle masted extended fast mode setting and not playing games whilst idling?

It's a good idea to check the steam client to make sure steam acknowledges that a game is playing.

And it might just be that the Steam servers are up and down like a yo-yo over the holiday period, not a good time to idle games.

https://psteamcommunity.yuanyoumao.com/groups/idlemastery/discussions/0/1290691937722380084/

Best not to run it at the same time as a VAC protected game or other game security systems but otherwise it should be ok.

https://psteamcommunity.yuanyoumao.com/groups/idlemastery/discussions/0/1290691937722380084/

Don't run IM from inside a zip file.
Delete IM's appdata.
see:
https://psteamcommunity.yuanyoumao.com/groups/idlemastery/discussions/0/133257636766989675/