Mock not working with Jmockit older version

I was trying to mock findOne & findByHeaderId methods of all the implementation of two repository interfaces as below. It was successfully mocked with Jmockit version 1.17 or greater.

when I changed the version to less than 1.17, DetailsRepo is unable to mock. But still Header repo method is mocked. Why mocking is not happening for Details repo method?

@Test
@Rollback(true)
public <T extends JpaRepository<Header, Long>, U extends DetailsRepository> void mock_test() {

            // --mocking Header repo
            new MockUp<T>() {
                @Mock
                public Header findOne(Long id) {
                    // -- mocking logic
                    Header header = new Header();
                    header.setId(Long.MAX_VALUE);           
                    header.setRemarks("testing");
                    System.out.println("********** HeaderRepository Mocked ***********");
                    return header;
                }
            };

            // --mocking Details repo
            new MockUp<U>() {
                @Mock
                public List<Details> findByHeaderId(Long id) {
                    List<Details> list = new ArrayList<Details>();
                    //  -- mocking logic here
                    System.out.println("********** DetailsRepository Mocked ***********");
                    return list;
                }

            };

            Details detailsTO = detailsServicesImpl.getDetails(Long.valueOf(Long.MAX_VALUE));
            Assert.assertEquals(Long.MAX_VALUE, detailsTO.getId().longValue());
}


@Repository
public interface DetailsRepository extends JpaRepository<Details, Long>, BatchRepository<Details> {

    List<Details> findByHeaderId(Long id);

}