I am afraid that I don't know the answer to that question. However, I understand that one of the satellite networks was rather unreliable (Iridium?). I suppose that network issues might have been the problem. We were on the Channel Islands and had unimpeded access to the sky and, evidently, one of Verizon's towers.

Verizon was marginal in that you had to stand in one spot, make a wish, spin around three times, and....access!