Project Keys Already in Use?

[Samantha Barton]

I have two projects: TEST and TEST2 (screenshot: https://www.screencast.com/t/TyUOoqJCVWzG)

I changed the key from TEST to TESTX for the project called "TEST". I am trying to change the key for the project called TEST2 from TEST2 to TEST but am getting an error saying the key "TEST" is already in use but project TEST, but it really isn't anymore, because I changed that project's key to TESTX (I hope we're following here). 

Any idea how I can fix / get around this?

[Gurpreet · Accepted solution]

You won't be able to create a new project with the old project key. The old project key will only be available if you delete the project it was previously associated with.

[Ryan Meinzer]

This isnt an answer.  OP said they changed the key, and it is still blocking.  I am having the same issue.

[Divya TV]

Even after changing the project key, I cant create a new project with  old key