Games redownload again and again in Google play store

I try to download 'clash of clans' but it keep download the game over and over again. Reboot phone still the same. Not sure why. Try download with 'mobomarket' but that 'clash of clans' have ads. Lot of it. Even I'm not playing the game, the ads still going to pop up. I don't like it. Can somebody explain why it keep download the game with 'Google play store' but not install it? My Android version say I can download the game but the game not installed. It just redownload the game.

What if other game become like this.

Hello, download here play store download the latest version.