Audible does not download audiobook on mobile data

I'm using Audible for Android, and when I purchased a book, I'm not able to download it over mobile data. I have ensured that background data is enabled both system-wide and for Audible, but Audible still would not download. After I tap *Continue* on the "Data Usage Notice", Audible only shows the following on the book: - Waiting to download... - Retrying 2 of 5 - Retrying 3 of 5 - Retrying 4 of 5 - Retrying 5 of 5 - Retrying 6 of 5 *(huh?)* - **Invalid data format** Is there anything else I should do to have it download the audiobook over mobile data? Or is it possible to do it over WiFi only? (I can download over WiFi without any problem.) It is possible that my mobile network service provider actively blocks Audible downloads, however, there were no reports about this that I could find online. My device is OnePlus 2 running stock Android Marshmallow.