Fatal error: Uncaught Error: Call to undefined function wp() in /home/nr4dxonhypyy/public_html/wp-blog-header.php:16

Fatal error: Uncaught Error: Call to undefined function wp() in /home/nr4dxonhypyy/public_html/wp-blog-header.php:16 Stack trace: #0 /home/nr4dxonhypyy/public_html/index.php(17): require() #1 {main} thrown in /home/nr4dxonhypyy/public_html/wp-blog-header.php on line 16

I reinstalled WordPress, (upload the new copy on the site, and I made sure it's up to date) - equivalent to a manual update. After that website works well and I quickly make sure and update all the plugin and theme But suddenly I see approx 30 minutes the website have same error again I try this process again and again but Got the same error

Can anyone help me to figure it out

After that its started to work fine, so this problem is now fixed.