Website Down

From Today evening when I check my site, it shows the following error message.

“Fatal error: Uncaught Error: Call to undefined function wp() in /home/u913242022/domains/themoneytell.com/public_html/wp-blog-header.php:16 Stack trace: #0 /home/u913242022/domains/themoneytell.com/public_html/index.php(17): require() #1 {main} thrown in /home/u913242022/domains/themoneytell.com/public_html/wp-blog-header.php on line 16”

I contact my hosting provider, hostinger India and they informed that,Today many wordpress site faces the same issue and contact WordPress.

Request you to advise and help me to restore my site.

The page I need help with: [log in to see the link]