Make sure you entered a valid US mobile number. International numbers aren't supported.
Ensure your phone has service to receive SMS.
Check that the number isn't a VoIP or landline (texts won't deliver to those).
Wait up to 60 seconds. SMS can be slow!
Turn your phone off and on again to reset your connection to your carrier.
If none of that works:
Contact Member Support with your phone number and they can check if the send failed on the backend. You can reach out to our Member Success Team through the chat feature. Simply click the AlterMe icon in the bottom-right corner of your screen to start a conversation.
You may need to contact your phone carrier if the issue appears to be on their side. We'll let you know!