The message does not even identify its Sprint.  It just says they have questions about a recent call, so one does not even know who the caller is.  Sprint's customer service lacks. I cannot wait for my contract to be up so I can move to AT&T

I received two calls from this telephone number and during both times I was unable to answer the phone and the person or service did not leave a message. However, I did call the telephone number back, and it was an automated call from Sprint asking me to participate in a survey about my recent telephone experience. However, I do plan to call Sprint and ask them if this telephone number belongs to them. If yes, then why does it not appear on the Caller ID?