If you have upgraded your WHMCS version to use the WHMCS v7.5.0 with PHP 7.2, you might encounter issues during the FraudLabs Pro module installation. And, below is the error message shown.

WhoopsExceptionErrorException: The file /home/user/public_html/modules/fraud/fraudlabs_pro/fraudlabs_pro.php was encoded by the ionCube Encoder for PHP 5.6 and cannot run under PHP 7.2.
Please ask the provider of the script to provide a version encoded with the ionCube Encoder for PHP 7.2.

This is due to the old FraudLabs Pro package being encoded for PHP 5.6 which will no longer work for the latest WHMCS version running on PHP 7.2. To fix this issue, you will need to download the latest FraudLabs Pro package and re-install the module. Below are the steps to re-install the package.

1. Download the module file from https://marketplace.whmcs.com/product/630
2. Unzip the downloaded package.
3. There are several packages available for various PHP versions.
4. Copy php72/whmcs/includes/hooks/fraudlabs_pro.php (the downloaded package) into /includes/hooks/ folder (where your WHMCS installed).
5. Copy php72/whmcs/modules/fraud/fraudlabs_pro folder (the downloaded package) into /modules/fraud/ folder (where your WHMCS installed).
6. On WHMCS admin page, click on the Setup->Fraud Protection
7. Select Fraudlabs Pro from the dropdown list and click on Go
8. Configure the details for FraudLabs Pro module setting.

The FraudLabs Pro module should be working fine in the WHMCS now.

*Note: The latest PHP version of 7.2 Release is recommended to be installed based on the recommended system requirements for running WHMCS 7.0 and later. You may find out more at WHMCS System Requirements docs here.