**Troubleshooting by tool:**
**WhatsApp:**
- Check WhatsApp connected on device
- Verify phone has internet
- Ensure not exceeding 200 messages/day
- Check recipients haven't blocked you
**SMS:**
- Android device online?
- App running in background?
- SIM card active?
- Sufficient SMS balance with carrier?
**Email (MailBots):**
- AWS SES credentials correct?
- Email/domain verified in AWS?
- Check spam score of email content
- Review AWS SES sending limits