You may see WhatsApp sends fail due to error code, 131026, when targeting Contacts. As outlined in Meta's documentation, below are the possible reasons for these failures:
For non-WhatsApp Mobile Numbers and Contacts utilizing an outdated WhatsApp version, Meta's documentation outlines steps to resolve these errors.
To determine if the send relates to WhatsApp Terms of Service update, you will want to follow these steps:
001245415

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