Explanation:

There are several reasons as to why an error may occur on your Magento-based site’s checkout page when Clearpay as the payment method is attempted.

Please refer to the Action section to further understand and resolve the challenge.

Actions:

Please review and follow the various reasons and solutions below:

• Incorrect API Credentials

  • Causes:

    • Invalid or outdated Clearpay API keys or Merchant IDs.

    • Sandbox credentials used in production, or vice versa.

  • Solution

    • Go to Stores > Configuration > Sales > Payment Methods > Clearpay.

    • Double-check the Merchant ID and Public/Private API keys.

    • Ensure you're using live credentials in production and sandbox credentials in staging.

    
    

• Clearpay Not Enabled in Admin

  • Cause: Clearpay is disabled in the backend config.

  • Solution

    • Go to Stores > Configuration > Sales > Payment Methods > Clearpay, enable the module.

    • Save and flush cache.

• Plugin or Extension Not Installed or Outdated

  • Cause

    • The official Clearpay module for Magento isn’t installed or is not the latest version.

    • Conflicts with other installed extensions.

  • Solution: Please ensure the official Clearpay plugin is installed, also to check Clearpay's official Magento documentation for version compatibility.

  
  

• Customisation on Magento CE Causing Conflicts

  • Cause: Custom code and modules on Magento Community Edition interfering with Clearpay logic or checkout flow.

  • Solution:

    • Please isolate the custom module by disabling it temporarily, revert any custom templates or JS files that override default payment or checkout behaviour, and check if customisation overrides layout XML that might remove or move Clearpay blocks.

    • Compare with a clean CE install and test behaviour, and co-ordinate with the developer to refactor custom logic to be compatible with Clearpay’s integration points.

    
    

• SSL Certificate Issues

  • Cause: No HTTPS - Clearpay requires secure connections.

  • Solution:

    • Ensure SSL certificate is installed and site is accessible via HTTPS.

    • Update Magento’s base URL settings to use https://.

    
    

• Country or Region Restrictions

  • Cause: Clearpay disabled for certain countries or regions.

  • Solution:

    • In Clearpay config, set “Allowed Countries” to either “All” or the specific countries supported by your Clearpay account.

    • Check if shipping/billing addresses fall within those allowed regions.

    
    

• Minimum/Maximum Order Value Limits

  • Cause: Order total outside Clearpay limits.

  • Solution: Check the cart subtotal and adjust the cart to fall within the limits.

  
  

Related Links: 

• Magento Forum

• Clearpay Magento Integration Guide