Can't uninstall and re-install torrent

[repeo]

I have been using torrent for years. Usually I install torrent and use and when I get a notification of updating the torrent, I uninstall the previous one and re-install it downloading. But I forgot to uninstall the previous one last time and after I had updated the latest torrent, I can't uninstall the torrent. It creates problems even after I click it to open. It says that there are multiple apps running. I just want to uninstall it and want to install a fresh copy of torrent. That's it. Please help me out. What should I do?