If you joined the website as a member, if you click the link https://secure.pitchero.com/account/settings/privacy and scroll down, you will see the following section.

"Chasetown FC Consent
I consent to my data being stored and processed by Chasetown FC for use in their management system which helps to organise the playing and enjoyment of sport for it's members."

There is a button which says "Leave Club" if you do not consent. This would remove your details from the club database.

If you wish to carry on using the website as a member, you do not need to do anything.