Hello, I need help to understand how is possible that someone has above 350 activity in the last 6-7 months, and no merit at all.
There are no guaranteed merits to be earned if someone's activity reaches a certain amount of time as long as nothing wouldn't give merit on his posts he can't get merit at all even it reaches a thousand activity.
And, is there any limitations for buying copper badge? (Limitation in number of posts)
There are no limitations, even a user has 0 posts or just Brand New member he can buy it. See examples below of users that buy the membership but has 0 posts, it's just so weird they just buy it by and just leave it, anyways I don't know the reason behind it, I just give you an example.
https://bitcointalk.org/index.php?action=profile;u=1375420https://bitcointalk.org/index.php?action=profile;u=1376189https://bitcointalk.org/index.php?action=profile;u=1254044