When I clicked download for the first time, a pop-up box prompted me to comment before downloading. Then after I commented, I clicked local download again but nothing happened. The page just refreshed. What is the reason?

Resource cannot be downloaded-PHP Chinese Network Q&A

When I clicked download for the first time, a pop-up box prompted me to comment before downloading. Then I commented and clicked local download again but nothing happened. The page just refreshed. What is the reason?