If you call LSAC and tell them how long it's been, they might just let you fax it. I had an LOR that was sent 11/13, then re-sent 2 weeks later, and neither ever showed up. Last week I had the prof fax it in and it showed up as processed that evening.
Both of my recs were lost by LSAC, so they had to be resent. One has showed up so far.