User Fields being populated during test execution

Hello,   My testers add details of the test case during the test execution.  (manual runner).    This same test will be used in the NEXT test cycle.

The details of the previous test cycle still exist. 

Please send suggestions of how to remove data after each test cycle.

Note:  the process to get the test case to each test cycle is a copy and paste.   (giving the test case, at least, a new test id number)

thanks!