It depends on the club but it would appear you’re being blocked. Do you have contact information in the headers of your request? Can you view the endpoint through the browser?
https://www.chess.com/announcements/view/breaking-change-user-agent-contact-info-required
So I was finding the API of a club and this error popped up. What do I do?
{"code":403,"message":"An internal error has occurred. Please contact Chess.com Developer's Forum for further help https://www.chess.com/club/chess-com-developer-community ."}