Ansible parallel task execution failing(async)

Hello guys , i am trying to run 2 tasks (both are import_tasks) parallely using async and poll but it is not running as expected. Tried async with invoking cmd or commands simply and that worked.
Can you guys give some suggestions?
Thanks,
Manash

If you could provide us playbook and error screen shots, that will help us to guide you better.

async does not affect imports nor includes, in 2.8 you will get an
error on include since it does not apply to it, for imports it is
inherited by all imported tasks, but the imports themselves will NOT
be async.