Email Sending/Receiving Debugger

Help me debug email sending/receiving issues.

**Email service/SMTP:** {{EMAIL_SERVICE}}
**Language/Framework:** {{FRAMEWORK}}

**Email sending code:**
```{{LANGUAGE}}
{{CODE}}
```

**Email template (if applicable):**
```html
{{TEMPLATE}}
```

**SMTP configuration (sanitized):**
```
{{SMTP_CONFIG}}
```

**Error or issue:**
```
{{ERROR}}
```

**Problem description:** {{PROBLEM}}

Please provide:
1. **SMTP Analysis**: Check SMTP connection and auth
2. **Email Headers**: Verify proper email headers
3. **Spam Issues**: Why emails might go to spam
4. **Template Rendering**: Check template variable rendering
5. **Fixed Code**: Corrected email sending code
6. **Deliverability Tips**: Improve email deliverability
7. **Testing Approach**: How to test email sending
8. **Error Handling**: Proper email error handling