There are many reasons of getting this error, 4 most common reasons are:
- PHP version issue
- WordPress core issue
- WordPress themes or plugins issue
- Server issue
Here we will explain how to fix these 4 issues.
- PHP version issue: Updating your PHP version can fix this issue. Log into your cPanel and go to multiPHP manager.
Here in the top you can see the current PHP version. Select your domain and chose PHP version you want from the drop down menu. Click on apply to change PHP version.
2. WordPress core issue: Updating your WordPress version can fix the issue. Log into your cPanel and go to WordPress manager. You can update and check your current version from there.
3. WordPress theme or plugin issue: If the issue is causing from your themes or plugins you can solve the issue by changing theme or deactivating the plugin. Log into your cPanel and go to file manager. Go to public_html folder. You will find a file named error log. Check your error log, the problem and the cause will be written there. You can solve the issue by taking action according to the error log.
4. Server issue: The error can occur for server issues. Contact with your hosting provider to fix this issue.