Poco No HD on Amazon Prime Video

Hey Guys, Yesterday I started watching something on Amazon Prime Video. After a while I realised the quality of the video was only SD. I then looked in the settings and saw that the app only lets me watch for a rate of 0,46GB/h. That is too low for HD streaming. My friend, whose got an Samsung, goes up to 1,8 GB/h. Anyone have the same problem? Maybe someone can tell me what to do? Thanks.