can't download any app from store on my nokia lumia 520

[Patel Yash]

hi....i have nokia lumia 520 windows phone and i have updated it and i have 8.1 os on it. one day i uninstall hike and try to download again but i can't i have try another app to download but i can't and It always stays on Pending and never starts the download. so what can i do?????