We would need to take a look at that for you, however please bear in mind we are on limited support until 3rd jan due to the holidays. If you can provide more information as to the user there, we can take a look
The error there is being returned from sendgrid. I would advise on asking them how best to resolve this issue, and if they can provide you with more information
I'm sure there is no need for the argument here guys. The suggestion is here in the feedback area, and will of course be read through as we do with all feedback
hCaptcha tends to be the most effective in terms of captcha solution. Of course that should be used in conjunction with other spam prevention measures.