Is it possible that the sending number is marked as spam with certain carries and being blocked that way?.. if so how can i find out to confirm this with said carries?.. also is there anyway to get that number unblocked with those carriers?
In addition to the API rate limit, phone number use is governed by the FCC. Currently, RingCentral provides local phone numbers, aka long codes, for SMS and are typically used for non-marketing person-to-person and small-group text use cases. Based on our experience, we recommend sending up to 500 SMS text per long code per day. If you wish to send more than this, contact us our support team to discuss your use case.