Cancellation Fee

So, I was only using this program for a day or so for an assessment of mine, and I was only using the free trial. Maybe I forgot about it, because then it went the free trial was over and suddenly I was paying for it. I then cancelled it, upset that I had to pay for it when I had only meant to use it that one time. But now another payment went through today where I find out that it hadn't cancelled like I thought, I'm still paying for it and that there's now a cancellation fee because this had been going on way past 14 days. This is apart of the annual paid montly subcription and I had to pay $150 for the cancellation fee because I think it's definetly not worth keeping it if I've only used it once, will probably never use it again, especially after this, and if keeping it meant that I would have to pay even more.