Solution#1
To enable the mysqli PHP extension, you can follow these steps:
1. Log in to your Hostinger control panel.
2. Navigate to the "PHP Configuration" section.
3. Select the "PHP Extensions" tab.
4. Find mysqli in the list of extensions and ensure it is checked or enabled.
5. Save the changes.
This should enable the mysqli extension for your PHP configuration.
Solution#2
Change PHP version from your current version to PHP 7.4.
1. Log in to your Hostinger control panel.
2. Navigate to Advanced > PHP Configuration > Select PHP version.
3. Click update button.
4. Refresh website.