See Help --> Ask a Question, or https://support.chess.com/customer/portal/articles/search?b_id=12321&q=cancel+membership or https://support.chess.com/customer/en/portal/articles/1444834-how-can-i-end-my-premium-membership-subscription-
How do I cancel my premium membership?

I'm a long time diamond member and have been told by Chess.com that since I don't play my games fairly I cannot challenge anyone to play until I improve my behavior, and I no idea what I did and who levied the charge

I'm a long time diamond member and have been told by Chess.com that since I don't play my games fairly I cannot challenge anyone to play until I improve my behavior, and I no idea what I did and who levied the charge
Probably something listed in the following:
https://support.chess.com/article/627-sportsmanship-policy

If I click on "Cancel My Subscription", will it cancel auto-renewal or cancel my current membership????????
https://support.chess.com/article/585-how-does-membership-renewal-work
Canceling the membership just cancels the renew and you'll keep the membership until it expires.

AntwicH kullanıcı adlı hesabimin Elmas üyeliğinin iptalini istiyorum
If you want to cancel, you can do that by following the instructions below.
https://support.chess.com/article/585-how-does-membership-renewal-work

Please can you cancel my membership and refund. Thank you. Helen Hawtrey.
You can cancel: https://support.chess.com/article/269-how-can-i-update-my-membership
If you want a refund, you'll have to open a ticket with support. There's a button on the following page to open a refund request:
https://support.chess.com/article/572-what-are-your-payment-policies-refunds-services-currency-etc
I activated a free trial of the premium chess membership and I cancelled it but it stills shows after the day I cancelled and it still shows the days after the ten day free trial wtf is going on

I activated a free trial of the premium chess membership and I cancelled it but it stills shows after the day I cancelled and it still shows the days after the ten day free trial ... is going on
If you didn't cancel before the trial converted into a full membership, that only cancels the automatic renewal, not the membership.

Hi please cancel my diamond membership I don't want to charge may credit card
You have to do it yourself.
https://support.chess.com/en/articles/8701397-how-does-membership-renewal-work
How to cancel premium membership ?