I am not able to update Apple ID settings

Sir, I am an Indian, Mine is iPhone 5s Model No: NF355VN/A1530, Serial Number: DN******RC7, Software version: 12.2

I am not able to update apple id settings

If i put my apple id password i am getting this message " Verification Failed There was an error connecting to the Apple ID Server" Try again

I tried many many times but not able to connect.

my all apps are not working

If i click any app message appers " UNABLE TO INSTALL Please try again later"

If i restore my backup also not working.

Please help

[Edited by Moderator]