src/Message.php
private function setRecipients(array $recipients)
    {
        if (count($recipients) === 0) {
            throw new InvalidArgumentException('At least one recipient required');
        }

        $this->recipients = [];
        foreach ($recipients as $recipient) {
            $this->addRecipient($recipient);
        }
    }
private function setRecipients(array $recipients)
    {
        if (count($recipients) === 0) {
            throw new InvalidArgumentException('At least one recipient required');
        }

        $this->recipients = [];
        foreach ($recipients as $recipient) {
            $this->addRecipient($recipient);
        }
    }
Sets/replaces list of recipients.

@param string[] $recipients A list of phone numbers in the one of formats: "+71234567890" or "71234567890".

@throws \InvalidArgumentException If one of recipients is not a string or format is invalid.