How to get messages from sprint iPhone 4S that was lost, now has no service?

I lost my iPhone 4S (through sprint) a while back, I did get a new replacement, however, when I turned the old phone on I did not receive the text messages I know I had gotten while the phone was lost ( it took about a week or so for me to stop looking and actually purchase a replacement.) I know I had some rather important texts coming in and now have no idea how I can retrieve them. It's set up to Wi-Fi, but has not shown any missed texts, and I do know for a fact I had been sent quite a few during this time. Any way to view them or get them back without going to sprint?

If the messages were sent over SMS, then i'm sorry. Those messages will not show up. However, if sent with another iPhone, then it should come in over a data network (Wi-Fi)