Compliance Test Suite (for USB 2.0 device) Fails (Enumeration Test)

Hi all,

I tried to run the compliance test suite (Command Verifier)
for our USB 2.0 device, all the tests expect Enumeration test
(last test) passed successfully.
But the Enumeration test always fails in the zeroth iteration.
If the test suite was run in 'debug mode', the Enumeration test
passes for any number of times. But in the 'Compliance test'
mode, all the enumeration sequences (like Reset, Get Device
descriptor, Set Address, Get Configuration descriptor)
runs for one time perfectly and device responds to them with
appropriate data and status stage was also completed sucessfully.
But after this there is no other responds from the host, and the test
was initimated as failed. In the report, it was mentioned "Enumeration
test fails at iteration 0"

Required Suggestions.
Thanks
VCSViswa