Plugin Causing conflicts and Intermittent Outages

I had to deactivate the plugin because it was causing intermittent outages and dramatically slowing my site down. Of course the same day I figured that out I was charged my subscription renewal. How do I go about getting a refund as I will not be using the plugin any longer. I would rather deal with spam than have my site perform so poorly.

The page I need help with: [log in to see the link]