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I think I know what happened, seems like you have to be very active to get dmania upvote. This is from the FAQ section:
How do I get upvotes from the dMania bot?
The dMania bot selects a random post on the Trending page every time he reaches 100% voting power. At the moment the bot selects a post every hour. The bot will select only posts with above average upvotes and rewards. To get an upvote from the bot, create great posts and collect rewards and upvotes from the community. Only users who are active on dMania and don't spam will receive upvotes from the bot.

Requirements to get an upvote
Don't spam. Maximum 20 posts in the last three days.
Upvote other posts. Minimum 5 upvotes on other posts in the last three days.
Collect above average rewards and upvotes. Posts with $0.01 rewards and one upvote won't receive an upvote from the bot.
Every user receives maximum one upvote per day.