Comments with captcha not save in folder /user/data/comments

Hi,

I’m trying to configure the comments plugin with captcha validation, and simply, it doesn’t work, because it can’t write into folder of comments (usr/data/comments).

If I comment the lines which refers to captcha in the file comments.yaml, this working correctly, and write the comment into the folder comments. However, if I activate captcha again, the plugin work correctly.

Can anybody help me with this issue?
Thanks.