The Sims 4 Get to work code

I tried installing The Sims 4 Get to work expansion pack last night and entered the code.

I got the game to work but at about 8 hours in, the game crashed and I had to close the program.

When I looked on Origin, my 'Get to work' expansion pack wasn't in my library.

I looked on my computer and it hasn't been installed.

I tried to install it again but now its saying that my code for the game has already been used!?

I am 100% sure The Sims 4 is not on my computer and has not been installed.