"Recipient phone number is invalid or recipient does not want to receive SMS" error and Contacts with DoNotSms preference failing to filter out during Mass Sms in 5.x
"Recipient phone number is invalid or recipient does not want to receive SMS" error occurs during individual SMS. https://civicrm.stackexchange.com/questions/25478/clickatell-sms-recipient-phone-number-is-invalid-or-recipient-does-not-want-to. Contacts marked as 'donotsms' is not filtered out during mass SMS.
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