You might be interested in these frequently answered questions.
If you have fixed the problem with your system, you may request removal. You should only do this if you are in charge of your mail system—if you are an end user and do not manage your own eMail, you should contact your postmaster to request removal.
Most lists are self-service. Once you indicate that your mail servers are configured correctly by requesting removal, we will send you an eMail to your postmaster address (for the DSN and postmaster lists) or abuse address (for the abuse list). If you request removal from one of these lists and do not receive a removal request to the appropriate address, please enquire after verifying that your system does indeed support eMail to the postmaster and abuse addresses (in a case-insensitive manner) and that you are not filtering eMail to these addresses. Other lists will be processed with a delay.
You may only request removal from a given list once within a seven-day period (or once within an eight-week period for WHOIS2).