Asana offers printing but in just two, inflexible ways: Project actions menu > Sync/Export > Print to print all tasks, and Task actions menu > Print to print one task. I recommend you Try these troubleshooting steps, then please create a support ticket: see How to contact our Support Team.
As @Herve_Buisset kindly mentioned, you can also consider Asana2Go (Disclaimer: I’m the creator):