Steam Key in use?!

So, I just converted my regular key to a Steam key. Went to apply it to my Steam account and got a note that it's a duplicate product code (see below.)

Any suggestions? Tried searching about this issue to no avail.
Edit:
Leaving the above for completeness' sake, but it's been fixed. Got an amazingly rapid response from support too! Thanks guys. <3

Any suggestions? Tried searching about this issue to no avail.
Edit:
Leaving the above for completeness' sake, but it's been fixed. Got an amazingly rapid response from support too! Thanks guys. <3