Accepted, delivered, failed - what do they mean?

Steps

1. Accepted: the SMS gateway or email server took the message. It is not yet a delivery.
2. Delivered: the provider's delivery report confirmed it. Failed: the provider refused it or reported it undelivered (the reason is shown).
3. Give your SMS provider the delivery reports address from Settings → Hours, SMS & notifications so delivered and failed come in.

Good to know

• WhatsApp only accepts free text for people who wrote to you in the last 24 hours; others need an approved template - otherwise the message fails.