cannot recieve incoming calls

[metrocitygirl]

Okay so I am running my magic jack on a pc. When some people call me it works fine and I am able to receive the call, but for some reason when my boyfriend is calling in it doesn't work...it gives him an error message on the phone. I thought maybe it's because his service provider is sprint, but I had a friend who is also with sprint call to test it out and she got through fine. Does anyone know how to solve this problem?? Any help would be greatly appreciated. Thanks!

Lauren