WooCommerce Expert Needed to Fix Website Issues

Need a WooCommerce expert to fix checkout issues on an existing website. The main problem is that customers are unable to complete purchases, and the payment gateway is not working properly. You will review the current setup, identify the root cause, and implement a reliable solution so checkout functions smoothly. Please share relevant experience with WooCommerce troubleshooting and payment gateway fixes, along with examples of similar issues you have resolved.