If a Contract can be edited, there will be a red X. If there is a padlock Icon instead this means the Contract is attached to a User(s).  

You remove Contracts within an Individual Students record via navigating to:
  1. onBoard > People Finder > Search for the name of the Candidate
  2. Select the Contracts Tab and click the X to remove the Contract from this User

Or

You can remove Contracts with all the Contracts listed for all Users, to do this, navigate to:
  1. onBoard >  Process > Manage Contracts.
  2. Under Select Filter Options, filter on the School Year and Contract Type
  3. Click View
  4. Click Delete next to any records that appear on the right to remove their contracts