Fix WordPress Contact Form Issue

My WordPress site using Contact Form 7 is experiencing issues. Customers are not receiving email confirmations when placing orders, and there's an error message when trying to send the form.

Requirements:
- Troubleshoot and resolve the error message
- Ensure email confirmations are sent to customers
- No recent changes made, so the issue is likely internal

Ideal Skills:
- Expertise in WordPress and Contact Form 7
- Strong troubleshooting skills
- Familiarity with WordPress email configuration