Product: Mobile > Cell Phones > Sprint Cell Phones > SPH-A600
The Preferred Roaming List or the PRL is the cell sites that your phone utilizes while in use. If this is not up to Sprints latest PRL, then dropping calls are more common. This can be updated by pressing *2 and Talk. This will connect you to sprints automated service. Select 2 for updating your Roaming capabilities and your problem may be resolved.
For more information on the SPH-A600 click here.