Failed payments are usually caused by a missed configuration step during integration of the new plugin: Express Cards via PayMongo. Kindly check if you were able to do the following 3 crucial steps to ensure that your plugin is working correctly:
1. Go to your Shopify settings and continue to the Payment providers section, search for Express Cards via PayMongo and click "Activate".
2. On your Shopify Settings page, go to Payments and click "Manage" under Payment capture.
3. Select "Automatically at Checkout" and click "Save".
⚠️ Please note that the Express Cards via PayMongo plugin doesn't support the Hold-then-Capture feature. If you're planning to use Express Cards via PayMongo, make sure to disable the Credit/Debit Card via PayMongo plugin.
Feel free to reach out to [email protected] should you have any questions regarding this plugin!