I get 403 Forbidden error despite having all the SMS permission , is there anything that I am missing out on ?
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403 forbidden error occurs when the credentials are incorrect and authentication server reject the request. Check your credentials like client id, secret, phone number etc
Did you check if the phone number you are using is in E.164 format? Also, double check to see if you have hit the save button after you have selected SMS permission while giving permission to your app
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