No uploading

Install it on my site, don’t know why, not error message or any other sign. The page simply refresh itself after clicking the “submit” button. Nothing uploaded, nothing in Media Library.

bbPress version 2.5.8
WordPress: 4.5.1

Switched to Twenty Twelve theme, same result, no upload.

Any advice? Thanks

https://ww.wp.xz.cn/plugins/gd-bbpress-attachments/