If I understand correctly, all it takes is a few text messages from your client for you to incur huge bills on their behalf. I presume you're aware that text m

If I understand correctly, all it takes is a few text messages from your client for you to incur huge bills on their behalf. I presume you're aware that text messages are easy to fake. (https://en.wikipedia.org/wiki/SMS_spoofing https://en.wikipedia.org/wiki/SMS_spoofing) What controls do you have in place to prevent fraud?