Well, the answer is deceptively simple...
You are dead.
It shows you were 'lost at sea' and therefore it will not go any further...
You can get out of that by going into the regular game, loading a save before it...finishing out that patrol, and then it should let you back in.
UNLESS you have never really started a career...and as I recall, you have to do something before you can use it...
NealT