SiteGround Staging Issues – Fatal Error

Hello! Whenever I push my site live from SiteGround’s staging platform, I receive the following error:

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

Would anyone have any insight into what is causing this error? I disabled all plugins and still received the error. SiteGround said they are unable to assist. Thanks!

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