Installation Codes

I purchased SIMS 4 on 4th October 2014, but because our computer was in for repair at the time of purchase I installed it on to my friends computer on the 5th October 2014, and i have therefore been unable to install it on to my computer now that I have it back.  When i tried to install it on my computer it was telling me that the code has already been used, so my friend has since un-installed it from her computer but because the code has already been used the game i purchased is now unusable.

Is there any way round this.  I have proof of purchase for the game and also proof that my computer was in for repair at the time of the original installation.

Thanking you in anticipation.