我最近迁移了我的wordpress网站，现在我收到http错误500。调试日志显示：

PHP Fatal error:  Uncaught Error: Call to undefined function update_option() in /home/sweetsixsteen/public_html/wp-includes/functions.php:3
Stack trace:
#0 /home/sweetsixsteen/public_html/wp-settings.php(98): require()
#1 /home/sweetsixsteen/public_html/wp-config.php(110): require_once(\'/home/sweetsixs...\')
#2 /home/sweetsixsteen/public_html/wp-load.php(37): require_once(\'/home/sweetsixs...\')
#3 /home/sweetsixsteen/public_html/wp-blog-header.php(13): require_once(\'/home/sweetsixs...\')
#4 /home/sweetsixsteen/public_html/index.php(17): require(\'/home/sweetsixs...\')
#5 {main}
  thrown in /home/sweetsixsteen/public_html/wp-includes/functions.php on line 3
[16-Sep-2017 01:23:33 UTC] PHP Fatal error:  Uncaught Error: Call to undefined function update_option() in /home/sweetsixsteen/public_html/wp-includes/functions.php:3
Stack trace:
#0 /home/sweetsixsteen/public_html/wp-settings.php(98): require()
#1 /home/sweetsixsteen/public_html/wp-config.php(110): require_once(\'/home/sweetsixs...\')
#2 /home/sweetsixsteen/public_html/wp-load.php(37): require_once(\'/home/sweetsixs...\')
#3 /home/sweetsixsteen/public_html/wp-blog-header.php(13): require_once(\'/home/sweetsixs...\')
#4 /home/sweetsixsteen/public_html/index.php(17): require(\'/home/sweetsixs...\')
#5 {main}
  thrown in /home/sweetsixsteen/public_html/wp-includes/functions.php on line 3

我希望能得到一些帮助，因为我是新手，不知道会出什么问题。它可以修复吗？