I don't know the mechanism, but we send a fax to the NIHB for approval. Sometimes we follow-up three or four days later and say that we sent an approval and ask if there is any response. They say they didn't get it. Well, I know I sent it and I have confirmation that it was sent, but they haven't received it, so we have to start the process again. Then, I believe they would fax the document to the doctor's office. The doctor's office would fax it back to NIHB and then NIHB would fax us back at the pharmacy.
Yes, it can get lost. The network or the fax is busy, or whatever it is. It does happen that faxes get lost.