It is a known bug, next event is at 20 working days, every works fine till you play the first event, then the count of working days goes up to 24 so you miss the trigger for the second event to play (it only triggers at the 20th day)
To solve it you must edit your own savegame and change the variable 702 "dias trabajados" (days worked) to "20" then the event should trigger next tiem you go to work. To edit your savegame use
You must be registered to see the links
, if you have any problems or cant handle the savegame editor ask again