I tested my query to make sure it works, but the card colour configuration won't let me save it. There is no error message, however, so I don't understand what I'm doing wrong.
Welcome to Atlassian Community!
Just for us to better understand and help you with this issue, it would be great if you could share with us a screenshot of the error message.
You can also share the JQL with us, so we can test on our local site.
For more details about Card Color, please check our documentation:
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