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WhatsApp error 131021: sender and recipient are the same

Error 131021 means the sender and the recipient are the same number. WhatsApp does not allow a business number to message itself, and the cause is nearly always a test message addressed to the connected number rather than to a second phone.

131021

Meta's code for a send where sender and recipient match.

1

Numbers you need beyond the connected one in order to test sending.

0

Configuration changes that can make self messaging work.

Why it happens

Because the first thing anyone does after connecting a number is send a test message, and the only number they have in front of them is the one they just connected. It is a reasonable instinct and the platform refuses it.\n\nThere is no setting to change. Self messaging works in the WhatsApp consumer app as a notes to self feature, and it does not exist through the API.

How to test properly

With a second number, and a little care about which direction you are testing.

  • Use a personal phone as the test recipient. Any WhatsApp number other than the connected one works.
  • To test sending freely, have the test number message the business first, which opens the 24 hour service window.
  • To test outside that window, send an approved template, which is the only thing permitted there.
  • Do not register a second business number just for testing unless you need it: an ordinary consumer number is enough.

Common mistakes

  • Sending to the connected number to test. It is refused by design.
  • Assuming notes to self works through the API. It does not.
  • Testing a free form message without the customer messaging first, which fails with 131047 instead.
Doing this with EasyCoexistence

EasyCoexistence connects a number in minutes, so testing with a second number is a short detour rather than a second onboarding.

Frequently asked questions

Can I message my own number?

No. WhatsApp does not permit it through the API.

Is there a setting for this?

No. It is a platform rule.

What should I test with?

Any other WhatsApp number, including a personal phone.

Why did my test then fail with 131047?

Because a free form message needs the customer to have messaged you in the last 24 hours.

Keep reading

WhatsApp error 131047: re-engagement messageError 131047 means more than 24 hours have passed since the customer last wrote, so free text will not deliver. What to send instead and how to avoid it.The 24 hour customer service windowWhat the customer service window is, when it opens and closes, what may be sent inside and outside it, and why replies inside it are free.WhatsApp Coexistence: the app and the API on one numberCoexistence runs the WhatsApp Business app and the Cloud API on the same number at once. What it changes, what it does not, and how a number gets connected.WhatsApp error 131009: invalid parameter valueError 131009 means a parameter was present with a value the endpoint does not accept. Common causes: locale codes, phone formats and enum values.WhatsApp error 131045: phone number not registeredError 131045 means the number is not registered for messaging. What registration is, why it is separate from onboarding, and how Coexistence handles it.WhatsApp error 133006: phone number not verifiedError 133006 means the number must be verified before it can be registered. How verification differs from registration, and what it requires.

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WhatsApp Error 131021