Scores do not work

The quiz itself functions fine while the questions are being asked and it’s easy to set up, but the scores show 0 out of 0 no matter how many questions you get right. There are 10 open ended (essay) questions, I made sure that every question has 10 points assigned. I made sure that every answer is spelled correctly. Some of the answers are very simple words like “hi” and “Dog” so I know I’m spelling them correctly. Yet the score is always zero. I tried disabling every other plugin on the site and it had no affect. I then tried changing the theme three times with no other plugins installed and that had no affect. I was going to buy the Pro version for some extra features, but I’m afraid to make the commitment without this being fixed. Can you help? I’ll even give you admin access if you want. If the problem is something I’m doing that’s fine but I need to know. Right now it looks like its the plugin.

https://ww.wp.xz.cn/plugins/watu/