If you've seen the error message that looks something like the below, then you're in the right place.
Unable to pick winner, please try later. If you keep seeing this, ensure your caption matches the giveaway rules you set.
This message appears when you attempt to draw a giveaway winner and the attempt was unsuccessful. The attempt was unsuccessful because we were unable to find a randomly selected winner that met your giveaway criteria (the giveaway rules you set).
This can usually be resolved by attempting to redraw a few minutes later. However, if you continue to see the message the issue might be that the criteria you set in your post may not match the criteria you set for the giveaway in POPSMASH.
Currently, the only way to fix this is to manually draw a winner. Though, in the near future we'll be adding a way to edit your giveaway rules.