I should count yourself lucky that you now have a spare! Hold onto it for the day when your old one packs in completely. Seriously you have done nothing wrong and it will be more trouble than it is worth for you to post it back to VM, and more trouble for them to account for its return.
Superuser 2016/17 Use Kudos to say thanks Mark answer as "helpful" only when the problem is solved Please don't send me private messages unless I ask you to. I do not work for VM. The advice I give is based on my best understanding of VM policy and practice. You rely on it at your own risk.