mag254 - is there a way to find out which provider im with?

i bought a mag254 a year ago from a guy locally, and paid in advance for a year for my inlaws. well the year is coming up, and i cant get ahold of the person i bought from. inlaws are happy with the service.. would like to stick with the same service if possible, but i'm not sure if i can tell which one it is

thanks.