Written answers to the things that actually come up when you’re working a list of phone numbers — delivery, registration, opt-outs and what the balance just paid for. If yours isn’t here, write in.
The questions this product generates, in roughly the order they come up
Sending and delivering are two different events — US carriers make the final call, and reitexter records the reason they gave. Open History, or the thread in Chat, and every recipient carries its own status. The usual reasons: the carrier filtered it as spam, the number you sent from isn't registered for 10DLC, the recipient is a landline that can't receive text, that person replied STOP at some point, the number is disconnected, or you hit a daily sending cap. A message that ends in failure is refunded to your balance automatically — you are not charged for traffic that never arrived.
Send the number you sent from, one recipient it failed for, and roughly when — that’s usually enough to find it in the delivery records on the first pass.