Zend certified PHP/Magento developer

Magento EE1.14 Order View not showing order details PHP 7.4

I just updated my PHP version from 5.6 to 7.4. I didn’t apply a security patch for Magento because most of the core code has been customized to work for our websites. I have made changes in all the files mentioned by the patch though. Now the problem I am facing is that whenever I click on an order it opens an empty page. Does not display any errors on system or exception log even after Magento backend debugging was enabled. Any help would be appreciated.thanks!