Did you win the achievement for the second time? Cause if you won the same cheevo twice, than you won't get rewarded for it twice. The counter on how many times you won said cheevo will only go up.
Mecha Mario -> RE: [PENDING] Daily Champion 2v2 (5/22/2015 14:11:23)
If you won the Daily Champion 2v2 a second time, the only thing that should be different is that your achievement for 2v2 Daily should be updated to reflect how many times you won it.