I would like a replacement controller or a refund for my controller I sent off

I sent my Xbox Elite Controller Series 2 off for repair to Microsoft for a replacement controller in October and UPS has said it was delivered to my address but it wasn't. I have phoned Microsoft and they have confirmed that UPS have lost my package. I would like a replacement controller or a refund for this. How should I go about this in the quickest way possible as I've been waiting too long for this replacement.

:)