Troubleshooting
"(#100) Invalid parameter" on one contact
This almost always means your own connected WhatsApp number is in the audience. WhatsApp never delivers a business message to the sending number.
Last reviewed 9 November 2026
When a campaign fails for exactly one contact with (#100) Invalid parameter, that contact is usually the same number you are sending from. WhatsApp does not allow a business number to message itself.
Fix
- Open the contact and compare it with the number on your channel card in Settings → WhatsApp.
- Remove the number from the group or mark it opted out so it is excluded automatically.
PayPerWA now detects this before sending and marks the message as Own number and refunds PayPerWA's fee, so the rest of the campaign is not affected. To test a template on yourself, send it to a second phone instead.
Still stuck?
Chat with a person on WhatsApp or raise a ticket with a screenshot. We reply on every ticket by email.