Text messages can have a status of failed for a variety of reasons:
invalid phone number (may be a landline or a home phone)
network issues with the recipient’s cell phone carrier
the cell phone or destination device is out of funds
recipient has blocked your number
recipient has message filtering enabled on their device (this means that incoming text messages from a number that is not a contact in their cell phone is rejected or separated into a spam type folder and may be hidden!)
the cell phone has insufficient memory
high traffic on cell network
rejected by carrier due to message including a suspicious link (bit.ly and goo.gl)
Carrier violations:
Cell phone carriers such as T-Mobile, AT&T and Verizon filter text messages to minimize spam. Cell phone carriers use AI (artificial intelligence) to filter text messages. Here are some of the reasons that text messages may be filtered or rejected:
high opt out rates and blocking of your number by recipients
large sending volume averaging over 200 individuals per day
low reply rate - are your recipients replying to your messages?
long messages with links
unbranded shortened URLs like bit.ly, tinyurl.com
words like cannabis, CBD, gummies will cause cell phone carriers to block your texting number
Here is a list of words that could flag your number: click here
Tips to improve deliverability:
ask the patient to save your office phone number as a contact in their cell phone
ask the patient to text the word "START" to your texting number
ask the patient to check their message filtering settings
send texts that encourage a reply