I need to unfile some CIS returns however my system does not have the unfile option.

Hello Kim Francis, 

Welcome to the Community page, 

This article has the steps to unfile. You should see the option button for the CIS unfiled as long as the return isnt rejected . If the return is rejected then you will need to ring the support line on 0808 234 5337 so they can get it unfiled for you.  The line is open mon to fri 8am to 7pm and is free from any UK mobile or landline.