Sandisk mobile ultra microSDXC 64GB class 10

I had given the card id of my Sandisk Class 10, 64Gb micro sd card to SanDisk for verification.  They confirmed I got a geniue one.  But after using the ATTO benchmark software to test its performance, the  average write/read speed is only reached  6.35 Mb/s and 18.99Mb/s respectively.

Have anyone carried out the similar test too?