Hi, i’m having erros trying to call Twilio API Request, the error that appears is “{"code":21604,"message":"A 'To' phone number is required.","more_info":"https://www.twilio.com/docs/errors/21604","status":400}”.
I tried a lot of forms to add the ‘TO’ Parameter without result.
I attach the configurations of the step
Thank you for your help.
Hi
Please link to the Twilio API endpoint documentation you used to configure the API request.
This is the information, this is in my Twilio account, probably it doesn’t public.
The response is
201 - CREATED - The request was successful. We created a new resource and the response body contains the representation.
{
"account_sid": "AC00812c3f10e0864cfa0b91f3a921de48",
"api_version": "2010-04-01",
"body": "Your appointment is coming up on July 21 at 3PM",
"date_created": "Fri, 09 Aug 2024 21:35:09 +0000",
"date_sent": null,
"date_updated": "Fri, 09 Aug 2024 21:35:09 +0000",
"direction": "outbound-api",
"error_code": null,
"error_message": null,
"from": "whatsapp:+XXXXXXXXXX",
"messaging_service_sid": null,
"num_media": "0",
"num_segments": "1",
"price": null,
"price_unit": null,
"sid": "SM8e1bd585b5ddb3d045553b5289a08b1e",
"status": "queued",
"subresource_uris": {
"media": "/2010-04-01/Accounts/AC00812c3f10e0864cfa0b91f3a921de48/Messages/SM8e1bd585b5ddb3d045553b5289a08b1e/Media.json"
},
"to": "whatsapp:+XXXXXXXXXXXX",
"uri": "/2010-04-01/Accounts/AC00812c3f10e0864cfa0b91f3a921de48/Messages/SM8e1bd585b5ddb3d045553b5289a08b1e.json"
}
First, remove the configured Query String Parameters.
Then check your parameter capitalization.
i chaged the configuration, but i have the same error.
{"code":21604,"message":"A 'To' phone number is required.","more_info":"https://www.twilio.com/docs/errors/21604","status":400}
Body needs to be valid JSON structure.
{
"From": "whatsapp:+1111111111",
"To": "whatsapp:+2222222222",
"Body": "Ahoy world!"
}
I has changed the body, the error persists.
For us to have current context, post screenshots with how your Zap step is configured in EDIT mode.
Send the screens
Send the DATA IN
method
method
POST
url
url
https://api.twilio.com/2010-04-01/Accounts/AC00812c3f10e0864cfa0b91f3a921de48/Messages.json
querystring
querystring
body
body
{ "From": "whatsapp:+XXXXXX", "To": "whatsapp:+XXXXXXXXX", "Body": "Ahoy world!" }
headers
headers
DATA OUTPUT
Full Response Data 
_full_response_data_
https://zapier.com/engine/hydrate/15095448/.eJw1zdEOgiAUxvF3OddQYKjoXc_RGmNwaExDJ7ByznePXN3-v7Pf2cBMIWFIKq0zQg9XIOBDTDoYVN5CL2TDJOeMgMkxTc8ccTkGXrOuFkIS0MZMuRD_KkTbEXAeR6uCfn5Z50eMhR5eenlE6LejqHny5ftSwm2DAddyGS9nW3GBznXU6UpSYYylmiGj3FnRomtMLWWxfvSCMY_plN4J9vu-fwCUeELN:1sdXeR:vMxDkjOILL3qbjivP4SA4hMvMTu8aBU5VcTKxhnXF0Y/
request
request
Request Method
method
POST
Request Url
url
https://api.twilio.com/2010-04-01/Accounts/AC00812c3f10e0864cfa0b91f3a921de48/Messages.json
Request Querystring
querystring
Request Headers
headers
Request Body
body
{ "From": "whatsapp:+XXXXXXXX", "To": "whatsapp:+XXXXXXXXX", "Body": "Ahoy world!" }
data
data
Request Data From
From
whatsapp:+XXXXXXX
Request Data To
To
whatsapp:+XXXXXXXX
Request Data Body
Body
Ahoy world!
response
response
Response Status
status
400
Response Headers
headers
Response Headers Date
date
Mon, 12 Aug 2024 16:12:07 GMT
Response Headers Content Type
content-type
application/json
Response Headers Content Length
content-length
127
Response Headers Connection
connection
keep-alive
Response Headers X Twilio Error Code
x-twilio-error-code
21604
Response Headers Twilio Concurrent Requests
twilio-concurrent-requests
1
Response Headers Twilio Request ID
twilio-request-id
RQ0772741ded6c3be2fe5e37fa0bf88358
Response Headers Twilio Request Duration
twilio-request-duration
0.032
Response Headers X Api Domain
x-api-domain
api.twilio.com
Response Headers Strict Transport Security
strict-transport-security
max-age=31536000
Response Headers Access Control Allow Origin
access-control-allow-origin
*
Response Headers Access Control Allow Headers
access-control-allow-headers
Accept, Authorization, Content-Type, If-Match, If-Modified-Since, If-None-Match, If-Unmodified-Since, Idempotency-Key, X-Pre-Auth-Context, X-Target-Region
Response Headers Access Control Allow Methods
access-control-allow-methods
GET, POST, PATCH, PUT, DELETE, OPTIONS
Response Headers Access Control Expose Headers
access-control-expose-headers
ETag, Twilio-Request-Id
Response Headers Access Control Allow Credentials
access-control-allow-credentials
true
Response Headers X Shenanigans
x-shenanigans
none
Response Headers X Powered By
x-powered-by
AT-5000
Response Headers X Home Region
x-home-region
us1
Response Body
body
{"code":21604,"message":"A 'To' phone number is required.","more_info":"https://www.twilio.com/docs/errors/21604","status":400}
data
data
Response Data Code
code
21604
Response Data Message
message
A 'To' phone number is required.
Response Data More Info
more_info
https://www.twilio.com/docs/errors/21604
Response Data Status
status
400
There are limitations to using the Twilio endpoint to be aware of that may be contributing to the encountered error.
Try setting the To line to before the From line in the JSON body.
How can change to call from webhook zapier functionality.
Did you try this?
{
"To": "whatsapp:+2222222222",
"From": "whatsapp:+1111111111",
"Body": "Ahoy world!"
}
Same result.
Help links for using WhatsApp in Twilio that may provide guidance on prerequisites:
https://help.twilio.com/articles/360007721954-Getting-Started-with-Twilio-for-WhatsApp
Hi, I cant send WhatsAPP Message whit zapier.
Then I try to send a basic SMS message using zapier and twilio. All is configured.
When send a message using curl (out of zapier) all is OK.
Here is the code.
curl 'https://api.twilio.com/2010-04-01/Accounts/AC00812c3f10e0864cfa0b91f3a921de48/Messages.json' -X POST \
--data-urlencode 'To=+XXXXXXXX' \
--data-urlencode 'MessagingServiceSid=MGd1ee3ff9fc2fb565fea055e7204b00ce' \
--data-urlencode 'Body=dfdsf' \
-u AC00812c3f10e0864cfa0b91f3a921de48:8AuthToken]
But when i try to send a message using zapier, an error appears.
Response Body
body
{"code":21604,"message":"A 'To' phone number is required.","more_info":"https://www.twilio.com/docs/errors/21604","status":400}
Hi, I cant send WhatsAPP Message whit zapier.
Then I try to send a basic SMS message using zapier and twilio. All is configured.
When send a message using curl (out of zapier) all is OK.
Here is the code.
curl 'https://api.twilio.com/2010-04-01/Accounts/AC00812c3f10e0864cfa0b91f3a921de48/Messages.json' -X POST \
--data-urlencode 'To=+XXXXXXXX' \
--data-urlencode 'MessagingServiceSid=MGd1ee3ff9fc2fb565fea055e7204b00ce' \
--data-urlencode 'Body=dfdsf' \
-u AC00812c3f10e0864cfa0b91f3a921de48:8AuthToken]
But when i try to send a message using zapier, an error appears.
Response Body
body
{"code":21604,"message":"A 'To' phone number is required.","more_info":"https://www.twilio.com/docs/errors/21604","status":400}
Hi 
I did some digging and found an existing feature request for the ability to support sending WhatsApp messages via the Twilio app, so that may be why it’s not working. I’ve gone ahead and added your vote to that feature request. While we can’t make any promises around when/if it will be implemented we’ll be sure to send you an email notification once it is.
In the meantime, I found a post on Stack Overflow here that gives details of how to do it using a Webhooks action in a Zap: 
Hopefully that helps to get your desired workflow up and running for now. 
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