HELP!!!!! app store doesnt work!!!

last week i tried to use whatsapp and it suddenly shut down, i couldn't go in and the app just froze. after reading that i need to delete the app and re download it, i deleted it but since then i couldnt download it from the app store [and after trying other apps, i could download or update any other app....!!!!], when i tried to download it from the cloud but it just showed that it was loading [the "loading circle" was moving but nothing downloaded and the icon didnt show on the home screen

few hours ago i updated the new ios 10.2.1 thinking it might help but now more apps are frozen [the apps are- "facebook", google drive" and "google map"]

i really dont know what to do, i tried everything that i could do and read online but nothing help

the photo is a screen shot after updating the new ios when discovering the other apps not working... [same exactly happened with whatsapp that made me delete it......]
any help?