We upgraded php version from 7.1 to 7.4 and 7.4 is selected in directadmin panel. But in places like wordpress the version still shows 7.1. What do you need to do?
In the CustomBuild section, you need to Build the PHP again.
Go to CustomBuild > Build Software > Build PHP
After that, it will should show up.
Also, if you have multiple versions of PHP installed, you have to set them up in order (1 being the default for all accounts) at CustomBuild > Edit Options The PHP options are the first set.