Site throws error when posting reply

Chrome console:

[email protected]?g-c268d195:1  POST https://getgrav.org/forum/support/how-to-use-cap-proof-of-work-captcha-found-in-form-plugin-settings-t9318 403 (Forbidden)
de @ [email protected]?g-c268d195:1
(anonymous) @ [email protected]?g-c268d195:1
s @ [email protected]?g-c268d195:1
[email protected]?g-c268d195:1 Response Status Error Code 403 from https://getgrav.org/forum/support/how-to-use-cap-proof-of-work-captcha-found-in-form-plugin-settings-t9318
O @ [email protected]?g-c268d195:1
he @ [email protected]?g-c268d195:1
fe @ [email protected]?g-c268d195:1
Dn @ [email protected]?g-c268d195:1
p.onload @ [email protected]?g-c268d195:1
XMLHttpRequest.send
de @ [email protected]?g-c268d195:1
(anonymous) @ [email protected]?g-c268d195:1
s @ [email protected]?g-c268d195:1

Same happens when replying to blog.

is this on a specific topic only? what do you mean "replying to blog"? in the blog post section? on a blog post page?

is this on a specific topic only?

I was trying to reply to https://getgrav.org/forum/support/how-to-use-cap-proof-of-work-captcha-found-in-form-plugin-settings-t9318. I've also tried to reply to another post, but don't recall which.

what do you mean "replying to blog"? in the blog post section? on a blog post page?

I was trying to add a comment to blog post https://getgrav.org/blog/grav-form-captcha-options

is it working now though? I think this was a cap 'captcha' failure, maybe transient?

The "Post Reply" and "Add Comment" didn't show any response and no reply/comment was added. Will try in both places.

Yes, I can add a Reply (have deleted it) and I can add a Comment to the blog post.

I have added refresh_nonce: true to the form configuration.. I think the nonce expired for you.