Cannot Uninstall or Deactivate

I noticed a few weeks ago that I cannot uninstall this plugin. I cannot deactivate it or uninstall it, and I need to be able to do that to check plugin-theme conflicts for some problems I’m attempting to solve. Can you help? Obviously I can go delete the files off the FTP server, but that causes more problems because then I have to start fresh afterward and I just need the plugin to behave properly — allowing me to deactivate or activate when needed. Thanks for your help!