why close it ? you have nothing to lose to leave your port there.
it's better to just stop submitting works to a site then close it.
leaving your port on a site that is not working for you still help you protect the copyright of your images.
the only time i would close an account is when i have to sell my images or if i am going exclusive elsewhere.
i hope this helps.
if you still wish to close, if there is no link on the account section to delete your account, you just need to submit a note to crestock via contact us
which will open this URL
https://www.crestock.com/contact.aspxor the email indicated there.
remember to do this logged into your crestock account.
take care.
