Configure Fallback

Create a fallback configuration in the OneXtel portal and attach it to WhatsApp or RCS campaigns.

This page walks through creating a fallback configuration in the portal, choosing a fallback mode, and enabling it on a campaign. For the trigger conditions and wait time/TTL concepts referenced below, see the fallback overview.

Create a fallback configuration

1. Log in to your account

   Sign in to the OneXtel portal.

2. Open Fallback

   Navigate to Fallback from the left-hand menu.

3. Add a fallback configuration

   Click Add Fallback.

4. Enter fallback details

   Enter a Fallback Name, choose a Mode (see below), and complete the remaining details for your primary, first fallback, and second fallback channels, including wait time.

5. Save

   Click to save the configuration.

   The system automatically generates a unique Fallback ID. This Fallback ID is the primary identifier used when sending campaigns and API requests with fallback enabled.

Choose a fallback mode

The platform supports two fallback modes.

Same Account mode

All channels involved in the fallback flow are configured and executed within the same account.

Example — WhatsApp → SMS. Both WhatsApp and SMS are configured under the same account.

Third-Party mode

Fallback traffic can be routed to:

1. Another account
2. Another product
3. An external provider / API

In this mode, you design your own API schema according to the third-party requirements:

1. HTTP Method — GET / POST
2. Endpoint URL
3. Headers
4. Payload Format

Third-party DLR callback

The platform provides a callback URL which the third-party platform must use to submit delivery status updates in the required format:

https://domain/cb/callback/tp

Enable fallback on a campaign

Fallback can be enabled while creating WhatsApp Campaigns and RCS Campaigns.

1. Open Additional Settings

   While configuring the campaign, navigate to Additional Settings → Enable Fallback.

2. Select the Fallback ID

   Select the required Fallback ID (Name) — the configuration you created above.

3. Fill in per-channel fields

   Depending on the fallback mode, the portal displays either the pre-defined channel fields (Same Account mode) or the fields from your configured payload schema (Third-Party mode). For each field you can provide static values, dynamic values, or a mix of both — see Dynamic field variables.

Same Account campaign configuration

All pre-defined fields are displayed during campaign setup.

SMS fallback fields

Field	Mandatory	Description
sender	Yes	SMS Sender ID configured for sending messages
recipient	Auto Derived	Recipient mobile number
type	Yes	SI, OTP, or SE — case-sensitive. TRANS, TXN and Promo are rejected as invalid type
messageBody	Yes	Content of the SMS message to be delivered
templateId	Optional	Template ID registered with the regulatory platform
entityId	Optional	Entity ID associated with the SMS template registration
unicode	Optional	1 = Unicode message, 0 = Normal text
custRef1 – custRef5	Optional	Custom reference fields for storing additional information

Template ID and Entity ID may be mandatory depending on country regulations. For DLT-registered SMS in India, you can leave both out only when template auto-match is enabled on the API key. OneXtel then matches the message body against your registered templates and fills in both IDs. Without auto-match, provide both.

WhatsApp fallback fields

Field	Mandatory	Description
WABA ID	Yes	WhatsApp Business Account ID
Template	Yes	Approved WhatsApp message template name
Recipient	Auto Derived	Recipient mobile number
Sender	Yes	Select WABA number / Number Pool from which the message will be sent
Language Code	Yes	Language code configured for the template
Template Components	Yes	Template parameters/components required to populate dynamic values in the WhatsApp template (header, body, buttons, etc.)

RCS fallback fields

Field	Mandatory	Description
Message Type	Yes	Define Transactional, Promotional, or OTP
Recipient	Auto Derived	Recipient mobile number
Sender Profile	Yes	Sender profile from which the message will be delivered
Custom Params	Yes	Dynamic parameters required to populate values in the RCS template
Template	Yes	RCS template configured for message delivery

Third-Party campaign configuration

For Third-Party fallback, all fields defined in your configured payload schema are displayed during campaign setup. You can provide static values, dynamic values, or mixed values, and map dynamic values from the uploaded recipient file — see Dynamic field variables.

Fallback Channel 1 and Fallback Channel 2 details can be added as per the fallback configuration. If third-party fallback is used, dynamic fields can be added with the specific channel name.

Sending fallback via API

To trigger the same fallback configuration from an API call instead of a campaign, include the fallback object — referencing this Fallback ID — in your Send API request body. See the Fallback API reference for the full request schema, parameters, and a sample request body.