Why can’t I take back my downvotes

in #hivelast year

OK I feel like shit. I’m a half blog I just accidentally downloaded somebody again this happened before and I can’t. I’m down vote them I can’t up vote them. And now I just feel bad because this person think so I don’t forget them when I have no ability to take it back.. if it’s going to be a vote that you can’t take back there should be at least the button should at least be far away from each other and not so close. This really sucks.