I went through the same experience every time I turn it off/on. It took me hours to activate the phone in the first place (many resets with Sprint on the phone). I finally went down to the Apple Store.They tried to exchange my phone with a "Service" phone but had issues activating that one. There was a Sprint Rep on-site, and he also was not able to resolve. I was sent back to point of sale store to get an exchange. Now I am waiting until the next shipment.... btw-we purchased 2 phones at the same time and the other one activated immediately and has no issues finding service after boot-up. I think it is a hardware issue.