Hi kamran1331
I've just tried it myself and it's working fine.
Perhaps it could be caused by any 3rd party plugin you might have.
In order to check this, I'd suggest you try to disable all your plugins except WooCommerce and ATUM and try that way. If it works, you can start enabling them back one by one until you find the cause.
I'd recommend you do so on a staging site (if possible).
Best Regards,
Salva.