You can do different stuff. For example, just rekey your lock at the locksmith. I had a similar problem about 3 years ago and this was actually what I did. There is no need in such expensive operation as people here propose. Just find a good locksmith. For example, when I was in the Dublin I called
https://www.locksmiths365.ie/ . You can find something similar and order new key. That will cost you something like $100, I think. Or more. I don't really know what is the cost in the U.S. but I don't think that it will cost you more. It's all about the locksmith, I'm telling you.