welcome to the forum
did you try loading an earlier save?
if that doesn't work, or isn't really a viable option, could you upload a savegame?
found in
...\Documents\My Games\Skyrim\Saves,
we'll need the skse and the ess of a manual (no quick- or auto-) save,
pack them to a rar or zip archive and attach them to a post here
EDIT
I looked through the bugracker and found it -
this unfortunately seems like a
known bug
but at least you can solve it on your end:
stuemper wrote:
Open the console, click on the servant and enter the follwing commands:
The servant should now speak to you