Help Grid Layout Not Working in android studio

[Sunil Bhukar]

I am create Grid Layout and CardView but card view not working i am use android studio 3.0.1 When I look in the Design View, everything looks right. But when I look up the run, I do not see the card on it. Showing text and background only on that. Please help me

i am facing troubles with the layout when i launch it on device with android version 5.1 Lolipop. please assist, it does not display a the cards views